94041-88-0Relevant articles and documents
Decarboxylative Alkylcarboxylation of α,β-Unsaturated Acids Enabled by Copper-Catalyzed Oxidative Coupling
Gao, Bao,Xie, Yinjun,Shen, Zhiqiang,Yang, Lei,Huang, Hanmin
, p. 4968 - 4971 (2015/11/03)
A facile and general method for copper-catalyzed decarboxylative alkylcarboxylation of cinnamic acids with dimethyl 2,2′-azobis(2-methylpropionate) has been developed. The scope and versatility of the reaction was demonstrated, and a broad range of substrates bearing electron-donating and -withdrawing groups on the aromatic rings were all compatible with this reaction to provide desired β,γ-unsaturated esters in moderate to good yields. Moreover, α,β-unsaturated acids with a carbonyl group on the γ-position of acrylic acids also smoothly proceeded to furnish the desired products in good yields.
Temperature-Dependent Alkylation of γ-Phenyl β,γ-Unsaturated Acid and Ester Systems in Hexamethylphosphortriamide-Tetrahydrofuran Solutions Using Lithium Diisopropylamide
Veen, Reinout H. van der,Cerfontain, Hans
, p. 342 - 346 (2007/10/02)
The reactivities of some β,γ-unsaturated carboxylic acids and their methyl esters toward alkylation with methyl iodide using the lithium diisopropylamide-hexamethylphosphortriamide (LDA-HMPT) systems in THF have been investigated.The methylation selectivity of pent-3-enoic acid (2) and (1,2-dihydro-3-naphtyl)acetic acid (6) on using 1.0 equiv. of methyl iodide is high, the α-mono- to α,α-dimethylation ratios at -78 deg C being >20.The selectivity is substantially lower for styrylacetic acid (4) and increases with increasing temperature from 2.3 at -78 deg C to 8.5 at -10 deg C.The occurrence of dimethylation is ascribed to intermolecular proton exchange between the monomethylated species IIa and the nonmethylated species Ia.For the β,γ-unsaturated esters the methylation selectivity is somewhat higher than that for the corresponding carboxylic acids.