131671-56-2Relevant academic research and scientific papers
Reactions of tin(IV) enolates obtained from O-stannyl ketyls under neutral free radical conditions
Enholm, Eric J.,Whitley, Paul E.,Xie, Yongping
, p. 5384 - 5390 (2007/10/03)
Under mild and neutral free radical conditions, an α,β-unsaturated ketone reacted with tributyltin hydride to produce an intermediate resonance-stabilized allylic O-stannyl ketyl. Upon subsequent hydrogen atom abstraction, a tin(IV) enolate was afforded which could be quenched with a variety of electrophiles and form new carbon-carbon bonds. Aldehydes react to produce aldol-type products and both intramolecular and intermolecular carbonyl addition reactions were investigated using this strategy. Using similar methodology, the tin(IV) enolate could be quenched in the presence of HMPA with various alkyl halides and α,β-unsaturated carbonyl compounds (Michael acceptors) to yield alkylated products in good yields. These reactions represent a very mild regioselective alternative to metal enolate formation which usually requires strong bases such as LDA or strongly reductive dissolving metal conditions to achieve success. New carbon skeletons for natural product synthesis can be readily constructed using this chemically neutral approach.
Tin(IV) enolates from allylic O-stannyl ketyls: reactions with alkyl halides and HMPA
Enholm, Eric J.,Whitley, Paul E.
, p. 559 - 562 (2007/10/02)
The mild free radical reaction of an α,β-unsaturated ketone and tributyltin radical produced a resonance-stabilized allylic O-stannyl ketyl intermediate. A subsequent hydrogen atom transfer produced a tin(IV) enolate which reacts readily with activated halides and HMPA to provide a useful and mild alternative to analogues Li-NH3 alkylations.
