In tandem reactions, cyclopropylcarbinols are obtained from allyloxylithium or -magnesium intermediates, generated in situ by alkylation of conjugated aldehydes, ketones, and esters as well as from allyl carboxylates or vinyloxiranes. Using this methodology, numerous fragrance ingredients and their precursors were efficiently converted to the corresponding cyclopropylcarbinols.
from α-substituted (homo)allyl alcohols. In tandem reactions, cyclopropyl carbinols are obtained from allyloxylithium or -magnesium intermediates, generated in situ by alkylation of conjugated aldehydes, ketones, and esters as well as from allyl esters and carbonates or vinyloxiranes. [¹] cyclopropanation - Barbier conditions - Grignard addition - alkyllithiumaddition - dibromomethane
[EN] CYCLOPROPANATION PROCESS<br/>[FR] PROCÉDÉ DE CYCLOPROPANATION
申请人:GIVAUDAN SA
公开号:WO2009023980A1
公开(公告)日:2009-02-26
A method for the preparation of cyclopropyl carbinols by cyclopropanation of unsaturated alcoholates, utilising a reagent system selected from (A) magnesium metal and dibromomethane, and (B) dibromomethane and a tertiary Grignard reagent, the reaction being carried out in the presence of an ether solvent. The process is useful, for example, for the preparation of ingredients for the flavour and fragrance industry.
[EN] ESTERS AND THEIR USE IN PERFUMERY<br/>[FR] ESTERS ET LEUR UTILISATION DANS LE DOMAINE DE LA PARFUMERIE
申请人:GIVAUDAN SA
公开号:WO2004050602A1
公开(公告)日:2004-06-17
This invention relates to unsaturated alicyclic carbonyl compounds of formula (I) [insert formula (I) here]wherein R is C1 to C4 alkyl; orR is vinyl or a linear, branched or cyclic C3 to C4 alkenyl;X is carbonyl or a divalent radical -(CMe2)- ; and Y is oxygen or a divalent radical -(CH2)- .
This invention relates to unsaturated alicyclic carbonyl compounds of formula (I)
wherein
R is C
1
to C
4
alkyl; or
R is vinyl or a linear, branched or cyclic C
3
to C
4
alkenyl;
X is carbonyl or a divalent radical —(CMe
2
)-; and
Y is oxygen or a divalent radical —(CH
2
)—.