1569-45-5Relevant articles and documents
Stereoselective allylation of ketones: Explanation for the unusual inversion of the induced stereochemistry in the auxiliary-mediated crotylation and pentenylation of butanone by DFT calculations
Tietze, Lutz F.,Kinzel, Tom,Schmatz, Stefan
, p. 1706 - 1712 (2009)
Auxiliary-mediated domino crotylations and pentenylations of butanone yield homoallylic ethers with two newly formed stereogenic centers. With our norpseudoephedrine-derived auxiliary, we observed the formation of anti isomers exclusively, and the nature
Zinc mediated allylation of aldehydes and ketones using allyl bromides and commercial zinc dust. the issue of regio- And stereoselectivity
Majee, Adinath,Das, Asish R.,Ranu, Brindaban C.
, p. 731 - 736 (2007/10/03)
An efficient procedure for the preparation of homoallylic alcohols has been achieved by a simple reaction of an aldehyde or a ketone with allyl bromide and commercial zinc dust in tetrahydrofuran. Excellent regioselectivity has been observed in the reaction of substituted allyl bromides.
Diastereoselectivity in the Addition of Crotylmagnesium Bromide to Unsymmetrical Ketones
Sjoeholm, Rainer E.
, p. 82 - 89 (2007/10/02)
Reactions of the Grignard reagent prepared from 1-bromo-2-butene (crotylmagnesium bromide, CH3CH=CHCH2MgBr) with 19 unsymmetrical ketones (R'RC=O;R'R; R=Me and R'=Et, i-Pr, c-Hex or t-Bu; R=Me, Et, i-Pr, c-Hex or t-Bu and R'=2-Fur, 2-Th or Ph) have been performed in order to study the diastereoselectivity of the reaction.All ketones gave two diastereomers of tertiary homoallyl alcohols formed by addition of an α-methylallyl group.With dialkyl ketones the major isomer had the anti configuration.With alkyl aryl(heteroaryl) ketones the syn isomer predominated.Thediastereoselectivites were quite low, except with t-Bu ketones which gave a maximum de of 84.Possible transition states are discussed and a mechanism is proposed based on our observations.
