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of charges in the betaine by such as lithium with greater solvation allowing more facile rotation in the betaine intermediate lowering the amount of reversibility |
the application of the johnson corey chaykovsky reaction in organic synthesis is diverse the reaction has come to encompass reactions of many types of sulfur ylides with electrophiles well beyond the original publications it has seen use in a number of high @@ profile total syntheses as detailed below and is generally ... |
many types of ylides can be prepared with various functional groups both on the anionic carbon center and on the sulfur the substitution pattern can influence the ease of preparation for the reagents ( typically from the sulfonium halide eg iodide ) and overall reaction rate in various ways the general format for the ... |
use of a sulfoxonium allows more facile preparation of the reagent using weaker bases as compared to sulfonium ylides ( the difference being that a sulfoxonium contains a doubly bonded oxygen whereas the sulfonium does not ) the former react slower due to their increased stability in addition the by @@ products of sul... |
the vast majority of reagents are at the ylide carbon ( either r1 or r2 as hydrogen ) reagents are much rarer but have been described |
if the ylide carbon is substituted with an electron @@ withdrawing group ( ewg ) the reagent is referred to as a stabilized ylide these similarly to sulfoxonium reagents react much slower and are typically easier to prepare these are limited in their usefulness as the reaction can become prohibitively sluggish examples... |
if the ylide carbon is substituted with an aryl or allyl group the reagent is referred to as a semi @@ stabilized ylide these have been developed extensively second only to the classical methylene reagents ( r1 = r2 = h ) the substitution pattern on aryl reagents can heavily influence the selectivity of the reaction as... |
if the ylide carbon is substituted with an alkyl group the reagent is referred to as an ylide the size of the alkyl groups are the major factors in selectivity with these reagents |
the r @@ groups on the sulfur though typically have been used to synthesize reagents that can perform enantioselective variants of the reaction ( see variations below ) the size of the groups can also influence diastereoselectivity in substrates |
reactions of sulfur ylides with ketones and aldehydes to form epoxides are by far the most common application of the johnson corey chaykovsky reaction examples involving complex substrates and' exotic' ylides have been reported as shown below |
the reaction has been used in a number of notable total syntheses including the danishefsky taxol total synthesis which produces the chemotherapeutic drug taxol and the kuehne total synthesis which produces the pesticide strychnine |
the synthesis of aziridines from is another important application of the johnson corey chaykovsky reaction and provides an alternative to amine transfer from though less widely applied the reaction has a similar substrate scope and functional group tolerance to the carbonyl equivalent the examples shown below are rep... |
for addition of sulfur ylides to enones higher 1 @@ 4 @@ selectivity is typically obtained with sulfoxonium reagents than with sulfonium reagents many electron @@ withdrawing groups have been shown compatible with the reaction including ketones esters and amides ( the example below involves a weinreb amide ) with furth... |
in addition to the reactions originally reported by johnson corey and chaykovsky sulfur ylides have been used for a number of related homologation reactions that tend to be grouped under the same name |
with epoxides and aziridines the reaction serves as a ring @@ expansion to produce the corresponding or the long reaction times required for these reactions prevent them from occurring as significant side reactions when synthesizing epoxides and aziridines |
several cycloadditions wherein the ylide serves as a nucleophilic carbenoid equivalent have been reported |
living using as the catalyst and ( ) methanide as the monomer have been reported for the synthesis of various complex polymers |
the development of an enantioselective ( ie yielding an enantiomeric excess which is labelled as ee ) variant of the johnson corey chaykovsky reaction remains an active area of academic research the use of chiral sulfides in a stoichiometric fashion has proved more successful than the corresponding catalytic variants b... |
the most successful reagents employed in a stoichiometric fashion are shown below the first is a bicyclic that has been employed in the synthesis of the β @@ adrenergic compound ( dci ) but is limited by the availability of only one enantiomer of the reagent the synthesis of the axial is rationalized via the 1 @@ 3 ... |
the other major reagent is a camphor @@ derived reagent developed by aggarwal of the university of bristol both enantiomers are easily synthesized although the yields are lower than for the reagent the ylide conformation is determined by interaction with the bridgehead hydrogens and approach of the aldehyde is blocke... |
catalytic reagents have been less successful with most variations suffering from poor yield poor or both there are also issues with substrate scope most having limitations with methylene transfer and aliphatic aldehydes the trouble stems from the need for a nucleophilic sulfide that efficiently generates the ylide whi... |
aggarwal has developed an alternative method employing the same sulfide as above and a novel alkylation involving a rhodium carbenoid formed in situ the method too has limited substrate scope failing for any electrophiles possessing basic substituents due to competitive consumption of the carbenoid |
the treaty of ciudad juárez was a peace treaty signed between the then president of mexico porfirio díaz and the revolutionary francisco madero on may 21 1911 the treaty put an end to the fighting between forces supporting madero and those of díaz and thus concluded the initial phase of the mexican revolution |
the treaty stipulated that díaz as well as his vice president ramón corral were to step down by the end of may and that he was to be replaced by francisco león de la barra as interim president and hold presidential elections those who had suffered losses due to the revolution would be the indemnified and there would be... |
significantly the treaty did not mention or institute any social reforms that madero had vaguely promised on previous occasions it also left the state essentially intact additionally madero supported the unpopular idea that all land disputes were to be settled through the courts staffed by the old judges a decision th... |
on june 7 1911 madero entered mexico city in october 1911 he was elected president under the banner of the partido along with josé maría pino suárez his new running mate as vice @@ president madero pushed aside francisco vázquez gómez the vice presidential candidate for the anti @@ party in 1910 as being too moderat... |
the rebellion against the government of porfirio díaz broke out in late 1910 after díaz had his rival francisco madero imprisoned and had announced his own victory in a falsified election madero's earlier vague promises of agrarian reforms had attracted many supporters he himself escaped from prison and fled to texas f... |
in the guerrero district of chihuahua pascual orozco attacked federal troops and sent dead soldiers' clothing back to díaz with the message te van las hojas más tamales ( here are the wrappers send me more tamales ) he then began operations which threatened ciudad juárez additionally political support for madero's ... |
at roughly the same time agrarian unrest in the state of morelos turned into a full blown rebellion under the leadership of the zapata brothers emiliano and |
encouraged by the news of the uprisings madero crossed the border back into mexico in february 1911 he was joined by pancho villa and orozco and in april the army began approaching ciudad juárez orozco and villa led the way with 500 men each while madero followed up with 1 @@ 500 riders the city was besieged by the end... |
at about the same time that villa and orozco were marching on ciudad juárez the zapatista revolt gathered strength and spread to the states of puebla tlaxcala mexico michoacán and guerrero on april 14 madero had emiliano zapata officially designated as his representative in the region however zapata was worried that if... |
zapata began the attack on cuautla on may 13 with 4000 troops against 400 elite soldiers of the so @@ called golden fifth the fifth cavalry regiment of the federal army the battle took almost a week and has been described as six of the most terrible days of battle in the whole revolution it consisted of house to hous... |
the successful capture of cuautla made zapata a hero to ordinary people throughout mexico and new corridos were written about him after zapata's taking of cuautla the federal government controlled only five states and some urban areas porfirio díaz himself later stated that while he felt that he could defend against vi... |
as early as march 1911 madero's representatives met in new york with díaz's finance minister josé yves limantour and the mexican ambassador to the us in order to discuss the possibility of peace between the two sides limantour proposed an end to the hostilities and offered an amnesty for all revolutionaries the resigna... |
faced with the siege of ciudad juárez and the outbreak of rebellion in morelos díaz and members of his cabinet became more willing to negotiate and launched a skillful peace offensive aimed at madero this was largely a result of panic among the large landowners associated with the díaz regime ( the hacendados ) and the... |
the moderate view within the díaz government was represented by jorge vera estañol who in a memo to the minister of foreign affairs wrote that there were two revolutions taking place in mexico a political revolution based mostly in the north whose aim was mostly to establish free elections and remove díaz himself from ... |
estañol's views represented those of the portion of the upper class which was willing to come to terms with at least a portion of the middle class in order to crush the peasant uprisings as exemplified by those of zapata which were erupting throughout mexico limantour who broadly agreed with estañol had the support of ... |
these social group were in turn opposed by the more reactionary elements within díaz's government mostly concentrated in the federal army who though that the rebels should be dealt with through brute force this faction was represented by general victoriano huerta who would later carry out an attempted coup d'état again... |
at the same time there was also disagreement among the rebels the left wing of the revolutionary movement represented by zapata and orozco ( villa for the time being tended to support madero ) warned against any possible compromises with díaz in the end their suspicions proved correct as the treaty that was eventually ... |
the most significant point of the treaty was that porfirio díaz and his vice president ramón corral resign and that de la barra acting as interim president organize free elections as soon as possible |
additionally the treaty stipulated that |
an amnesty for all revolutionaries be declared with the option for some of them to apply for membership in the rurales |
the revolutionary forces were to be demobilized as soon as possible and the federal forces were to be the only army in mexico this was in order to appease the army which had opposed a compromise with madero |
madero and his supporters had the right to name fourteen provisional state governors and to approve la barra's cabinet |
pensions were to be established for relatives of the soldiers who had died fighting the rebels |
policemen and judges as well as state legislators that had been appointed or elected under díaz were to retain their offices |
the treaty was signed on may 21 díaz resigned accordingly on may 25 francisco de la barra became the interim president madero entered mexico city on june 7 |
zapata however refused to recognize the interim government of de la barra and for the time being the fighting in morelos continued madero met with zapata on several occasions during june while initially zapata trusted madero with time he became increasingly concerned that the goals of his revolution were not being fulf... |
madero also earned the great displeasure of other revolutionaries including pascual orozco madero's first act after the treaty was signed was a gesture of reconciliation with the díaz regime as a result of the treaty he was given the right to appoint members of the la barra cabinet he chose mostly upper class maderista... |
orozco who saw himself as being instrumental in madero's victory over díaz was merely appointed as a commander of the rurales in chihuahua which increased his resentment when he tried to run for governor of the state madero supported his opponent abraham gonzález and eventually pressured orozco to drop out of the race ... |
the feast of the goat ( spanish la fiesta del chivo 2000 ) is a novel by the peruvian nobel prize in literature laureate mario vargas llosa the book is set in the dominican republic and portrays the assassination of dominican dictator rafael trujillo and its aftermath from two distinct standpoints a generation apart du... |
the novel follows three interwoven storylines the first concerns a woman urania cabral who is back in the dominican republic after a long absence to visit her ailing father she ends up recalling incidents from her youth and recounting a long @@ held secret to her aunt and cousins the second story line focuses on the la... |
readers are shown the regime's downward spiral trujillo's assassination and its aftermath through the eyes of insiders conspirators and a middle @@ aged woman looking back the novel is therefore a kaleidoscopic portrait of dictatorial power including its psychological effects and its long @@ term impact the novel's the... |
vargas llosa interlaces fictional elements and historical events the book is not a documentary and the cabral family for instance is completely fictional on the other hand the characters of trujillo and trujillo's assassins are drawn from the historical record vargas llosa weaves real historical incidents of brutality ... |
the feast of the goat received largely positive reviews with several reviewers commenting on the book's depiction of the relationship between sexuality and power and on the graphic descriptions of violent events |
a film version of the novel was released in 2005 starring isabella rossellini paul freeman and tomas milian jorge alí triana and his daughter veronica triana wrote a theatrical adaptation in 2003 |
the feast of the goat is only the second of vargas llosa's novels to be set outside peru ( the first being the war of the end of the world ) it is also unusual because it is the first to have a female protagonist as critic lynn walford writes of the leading character in the feast of the goat and also vargas llosa's sub... |
the novel examines the dictatorial regime of rafael leónidas trujillo molina in the dominican republic trujillo was in historian eric 's words a towering influence in dominican and caribbean history who presided over one of the most durable regimes of the twentieth century during the thirty @@ one years between his se... |
trujillo was officially dictator only from 1930 to 1938 and from 1942 to 1952 but remained in effective power throughout the entire period though his regime was broadly nationalist daniel comments that he had no particular ideology and that his economic and social policies were basically progressive |
the novel's title is taken from the popular dominican merengue al chivo ( they killed the goat ) which refers to trujillo's assassination on may 30 1961 merengue is a style of music created by lora in the 1920s and actively promoted by trujillo himself it is now considered the country's national music cultural critic... |
the novel's narrative is divided into three distinct strands one is centred on urania cabral a fictional dominican character another deals with the conspirators involved in trujillo's assassination and the third focuses on trujillo himself the novel alternates between these storylines and also jumps back and forth from... |
the feast of the goat begins with the return of urania to her hometown of santo domingo a city which had been renamed ciudad trujillo during trujillo's time in power this storyline is largely introspective and deals with urania's memories and her inner turmoil over the events preceding her departure from the dominican ... |
the second and third storylines are set in 1961 in the weeks prior to and following trujillo's assassination on 30 may each assassin has his own background story explaining his motivation for his involvement in the assassination plot each has been wronged by trujillo and his regime by torture and brutality or through a... |
the third storyline is concerned with the thoughts and motives of rafael leónidas trujillo molina himself the chapters concerning the goat recall the major events of his time including the slaughter of thousands of dominican haitians in 1937 they also deal with the dominican republic's tense international relationships... |
in the novel's final chapters the three storylines intersect with increasing frequency the tone of these chapters is especially dark as they deal primarily with the horrific torture and death of the assassins at the hands of the sim the failure of the coup the rape of urania and the concessions made to trujillo's most ... |
urania cabral and her father agustín cabral appear in both the modern day and historical portions of the novel in the year 1996 urania returns to the dominican republic for the first time since her departure at the age of 14 she is a successful new york lawyer who has spent most of the past 35 years trying to overcome ... |
rafael trujillo known also as the goat the chief and the benefactor is a fictionalized character based on the real dictator of the dominican republic from 1930 to 1961 and the official president of the republic from 1930 to 1938 and 1943 to 1952 in the feast of the goat vargas llosa imagines the innermost thoughts of t... |
trujillo's regime is supported by johnny abbes garcía the head of the military intelligence service ( sim ) a brutal man to whom many disappearances executions sudden falls into disgrace are attributed abbes and his intelligence officers are notorious for their cruelty particularly their habit of killing dissidents b... |
joaquín balaguer trujillo's puppet president is also a supporter and initially his seemingly innocuous character holds no real power following trujillo's death the calm and serenity of balaguer bring about real change in his character and general román comments that this insignificant man whom everyone had always consi... |
the storyline concerning the assassination primarily follows the four conspirators who directly participate in trujillo's death antonio imbert barrera is one of the few conspirators who survives the violent reprisals that follow trujillo's assassination imbert is a politician who becomes disillusioned with the deceptio... |
the feast of the goat's major themes include political corruption machismo memory and writing and power olga lorenzo reviewer for the melbourne age suggests that overall vargas llosa's aim is to reveal the irrational forces of latin tradition that give rise to despotism |
the structure of dominican society was hierarchical with strongly gendered roles rafael trujillo the ruler was a cruel dictator who haunts the people of santo domingo even 35 years after his death he is a true caudillo ruling with brutality and corruption he creates a personality cult in his capitalist society and enco... |
many of the assassins had belonged to the trujillo regime or had at one point been its staunch supporters only to find their support for him eroded by the state's crimes against its people imbert one of the assassins sums up this realization in a comment prompted by the murder of the mirabal sisters they kill our fath... |
according to literary scholar peter anthony the two important components of machismo are aggressive behaviour and hyper @@ sexuality aggressive behaviour is exhibited by displays of power and strength while hyper @@ sexuality is revealed through sexual activity with as many partners as possible these two components sh... |
in a display of both aspects of machismo trujillo demanded of his aides and cabinet that they provide him with sexual access to their wives and daughters mario vargas llosa wrote of trujillo's machismo and treatment of women [ h ] e went to bed with his ministers' wives not only because he liked these ladies but becau... |
trujillo's attempted sexual conquest of urania is an example of both political manipulation of agustín cabral and sexual power over young women however as trujillo's penis remains flaccid throughout the encounter and he is humiliated in front of the young girl the encounter fails to satisfy his requirements for machism... |
all of the novel's storylines concern memory in some sense or another the most apparent confrontation of memory is on the part of urania cabral who has returned to the dominican republic for the first time in 30 years and is forced to confront her father and the traumas that led her to leave the country at 14 she was t... |
memory is also important in the sections of the novel that deal with the assassins each recalls the events that led him to take part in the assassination of trujillo these incidents included the 1956 kidnapping and murder the 1960 murder of the mirabal sisters and the 1961 split with the catholic church these historic... |
but above all mario vargas llosa uses the fictional urania to facilitate the novel's attempt at remembering the regime the novel opens and closes with urania's story effectively framing the narrative in the terms of remembering the past and understanding its legacy in the present in addition because of her academic stu... |
in her treatment of the novel maría regina ruiz claims that power gives its wielder the ability to make prohibitions prohibitions that are reflected in history the study of which reveals what is and what is not told the government's actions in the feast of the goat demonstrate the discourse of prohibition foreign newsp... |
ruiz notes that writing also has the power to transform reality it brings the reader back to the past allowing the reader to comprehend myths or distorted stories told by historians ruiz contends that knowing the past is crucial to one's understanding of the present that takes us to postmodernism and argues that the fe... |
the construction of fictions surrounding the events of trujillo's regime allow a degree of freedom from the horrors that took places author julia alvarez contends that these events can only finally be understood by fiction only finally be redeemed by the imagination while richard patterson claims that vargas llosa a... |
the novel is a combination of fact and fiction blending together these two elements is important in any historical novel but especially in the feast of the goat because vargas llosa chose to narrate an actual event through the minds of both real and fictional characters some characters are fictional and those that are ... |
those within the regime are also a mix of fictional characters and real people president balaguer is real but the entire cabral family is completely fictional according to wolff vargas llosa uses history as a starting point in constructing a fictionalized account of trujillo's spiritual colonization of the dominican re... |
vargas llosa also built an image of the regime with the troubled historical events with regard to the historical accuracy of the book vargas llosa has said it's a novel not a history book so i took many many liberties the only limitation i imposed on myself was that i was not going to invent anything that couldn't have... |
the realist style of the feast of the goat is recognized by some reviewers as being a break from a more allegorical approach to the dictator novel the novel received largely positive reviews most of which were willing to accept sacrifices of historical accuracy in favour of good storytelling |
a common comment on the novel is the graphic nature of the many acts of torture and murder which are depicted in the novel vargas lets the reader see the realities of an oppressive regime with a degree of detail not often used by his compatriots in latin american literature as michael wood suggests in the london review... |
most reviews of the feast of the goat make either indirect of direct reference to the relationship between sexuality and power salon reviewer laura miller writer for the observer jonathan heawood walter kirn and michael wood each detail the connection between trujillo's gradual loss of ultimate control both over his bo... |
in 2011 bernard diederich author of the 1978 non @@ fiction book trujillo the death of the goat accused vargas @@ llosa of plagiarism |
an english @@ language film adaptation of the novel was made in 2005 directed by luis llosa mario vargas llosa's cousin it stars isabella rossellini as urania cabral paul freeman as her father agustin stephanie leonidas as and tomas milian as rafael leonidas trujillo it was filmed in both the dominican republic and in... |
the novel has also been adapted for the stage by jorge alí triana and his daughter veronica triana directed by jorge triana the play was put on ( in spanish but with simultaneous translation to english ) at español ( / chivo ) in new york in 2003 and the production moved to lima in 2007 a feature of the novel's stage... |
charles eaton obe afc ( 21 december 1895 12 november 1979 ) was a senior officer and aviator in the royal australian air force ( raaf ) who later served as a diplomat born in london he joined the british army upon the outbreak of world war i and saw action on the western front before transferring to the royal flying co... |
in 1939 on the eve of world war ii eaton became the inaugural commanding officer of no 12 ( general purpose ) squadron at the newly established raaf station darwin in northern australia promoted group captain the following year he was appointed an officer of the order of the british empire in 1942 he took command of no... |
charles eaton was born on 21 december 1895 in lambeth london the son of william walpole eaton a butcher and his wife grace schooled in wandsworth charles worked in battersea town council from the age of fourteen before joining the london regiment upon the outbreak of world war i in august 1914 attached to a bicycle com... |
on 14 may 1915 eaton transferred to the royal flying corps ( rfc ) undergoing initial pilot training at oxford while he was landing his maurice farman shorthorn at the end of his first solo flight another student collided with him and was killed but eaton emerged uninjured he was commissioned in august and was awarded ... |
eaton remained in the raf following the cessation of hostilities he married beatrice godfrey in st thomas's church at shepherd's bush london on 11 january 1919 posted to no 1 squadron he was a pilot on the first regular passenger service between london and paris ferrying delegates to and from the peace conference at ve... |
regarded as one of the raaf's most skilful cross @@ country pilots and navigators eaton came to public attention as leader of three military expeditions to find lost aircraft in central australia between 1929 and 1931 in april 1929 he coordinated the air force's part in the search for aviators keith anderson and bob hi... |
eaton was awarded the air force cross on 10 march 1931 in recognition of his zeal and devotion to duty in conducting flights to central australia in search of missing aviators the media called him the' knight errant' of the desert skies aside from his crash landing in the desert while searching for the kookaburra eat... |
following a 1937 decision to establish the first north australian raaf base in april 1938 eaton now on the headquarters staff of raaf station laverton and wing commander george jones director of personnel services at raaf headquarters began developing plans for the new station to be commanded by jones and a new squadro... |
once war was declared darwin began to receive more attention from military planners in june 1940 no 12 squadron was cannibalised to form two additional units headquarters raaf station darwin and no 13 squadron no 12 squadron retained its wirraway flight while its two flights of ansons went to the new squadron these wer... |
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