Preparation of functional styrenes from biosourced carboxylic acids by copper catalyzed decarboxylation in PEG

作者：Cadot Stephane; Rameau Nelly; Mangematin Stephane; Pinel Catherine; Djakovitch Laurent^*

来源：Green Chemistry, 2014, 16(6): 3089-3097.

DOI：10.1039/c4gc00256c

A general protocol for the copper-catalyzed decarboxylation of alpha,beta-unsaturated carboxylic acids in PEG, particularly of biosourced cinnamic acid analogues, is reported. Moderate to high isolated yields (31-96%) towards the styrene derivatives were obtained. For the first time, decarboxylation of a-amino acids to the corresponding amines was successfully performed with good to high yields and extended to the decarboxylation of a few condensed heterocyclic compounds. Both the use of PEG as a green solvent and direct separation of the pure product of the reaction by distillation permitted the reuse of the solvent and the Cu-based catalytic system over several cycles without deactivation. This was extended to the synthesis of 4-vinylguaiacol on the laboratory scale in an average 92% yield.

• 出版日期2014