2903-21-1Relevant academic research and scientific papers
1,4-DIASTEREOSELECTIVITY IN THE ADDITION OF ALLYLSTANNANES TO 1-ALKYL-2-OXOCYCLOHEX-3-ENEACETIC ACID METHYL ESTERS
Mobilio, Dominick,Lange, Barbara De
, p. 1483 - 1486 (2007/10/02)
Cyclohexanones 1 were allowed to react with allyltrimethylsilane and three allyltributylstannanes in the presence of titanium tetrachloride.Products 2 and 3 were formed in ratios ranging from 7:1 to 26:1 (2:3).Ratios resulting from the use of other Lewis acids support 4 as an intermediate which accounts for the observed stereoselectivity.
Ring Opening Reactions of Methyl 2-Siloxycyclopropanecarboxylates to Oxoalkanoic Acid Derivatives
Kunkel, Elisabeth,Reichelt, Ingrid,Reissig, Hans-Ulrich
, p. 802 - 819 (2007/10/02)
A great variety of methyl 2-(trialkylsiloxy)cyclopropanecarboxylates C1 - C31 are cleaved under very mild conditions and with excellent yields providing 4-oxoalkanoic esters D1 - D31 which are important synthetic building blocks.Even sensible esters with formyl, vinyl ketone, or trimethylsiloxy functions can be prepared.Corresponding to the regioselective synthesis of C isomeric pairs of D can deliberately be constructed.In the presence of an electrophile alkylating ring opening delivers 4-oxoalkanoates substituted in position 2, however, the degree of alkylation does not exceed 60percent.Several other cleavage variations allow syntheses of other 4-oxoalkanoic acid derivatives in effective one-pot procedures.
THE METHOXYCARBONYLALKYLATION AND METHOXYCARBONYLALKYLIDENATION OF SILYL ENOL ETHERS
Fleming, Ian,Iqbal, Javed
, p. 327 - 328 (2007/10/02)
Silyl enol ethers (1) react with the phenylthio(methoxycarbonyl)alkyl chlorides (2) in the presence of Lewis acids to give good yields of the γ-ketoesters (3); oxidative and reductive desulphurisations give the saturated (4) and unsaturated (5 or 6) γ-ket
