An intermolecular aza-variation of this reaction can be used to form spiroaminals, and Li and Corey note that the Staudinger intermediate can undergo this reaction to form heterocycles.
An intermolecular aza-variation of this reaction can be used to form spiroaminals, and Li and Corey note that the Staudinger intermediate can undergo this reaction to form heterocycles. One modification of this reaction uses a compound usually derived from the Arbuzov reaction, and that modification was further improved by Masamune and Roush by replacing NaH with lithium enolates, and by Gennari and Still using KHMDS and 18-crown-6 to improve stereoselectivity. An analogue of this reaction which uses silyl carbanions is named for Peterson, while another alternative to this reaction uses a compound containing a bridging chlorine and methylene group attached to dimethyl aluminum and titanocene. The currently believed mechanism states that the cis-intermediate undergoes the reverse reaction much faster than the trans intermediate, while that species, according to Maryanhoff and Reitz, undergoes isomerization in a process called "stereochemical drift," a fate that can be avoided by adding a lithium compound to convert the intermediate to a betaine. The initial preparation uses an SN2 reaction to add triphenyphosphine to an alkyl halide, which is then deprotonated to create a reagent with adjacent positive and negative charges. An alternative to using Tebbe's reagent, for 10 points, name this reaction which contains a ester variant named for Horner, Wadsworth, and Emmons and another variation which switches the stereochemical preference named for Schlosser, in which a phosphonium ylide is used to convert carbonyls to alkenes.
An intermolecular aza-variation of this reaction can be used to form spiroaminals, and Li and Corey note that the Staudinger intermediate can undergo this reaction to form heterocycles.
{Wittig} reaction (it’s the longest tossup ever!)