Schlosser, ManfredSchaub, Bruno2006-03-032006-03-032006-03-031982https://infoscience.epfl.ch/handle/20.500.14299/226801Mixts. prepd. from alkyltriphenylphosphonium bromides and powd. NaNH2 were stored indefinitely. Upon addn. of an ethereal solid, however, they immediately generated the ylide, which then reacted with aldehydes, ketones, and formates. The use of such instant ylide mixts. offered distinct advantages over conventional Wittig procedures: optimum yields (even with enolizable ketones), highest cis/trans ratios, largest range of applicability, shortest reaction times, and easiest handling. Thus, condensation of Ph3:CHEt with BzH gave 94% (Z)-PhCH:CHEt and 6% (E)-PhCH:CHEt. Among the approx. 30 compds. prepd. were cis- and trans-stilbenes, methylenecyclohexane, and cis- and trans-BuOCH:CHEt. [on SciFinder (R)]Wittig reaction (agents forstorable and ready to use ylides as); Ylides Role: RCT (Reactant)RACT (Reactant or reagent) (phosphorusstorability and use as Wittig reagents)ylide storage use; phosphorus ylide storage use; Wittig reagent storage use; aldehyde ylide condensation; ketone ylide condensation; formate ylide condensation; condensation ylide carbonyl compd; alkene synthesis storable ylideInstant-Ylid: ein lagerfähiges und gebrauchsfertiges Wittig-Reagenztext::journal::journal article::research article