METHOD FOR THE PREPARATION OF alpha-SUBSTITUTED ACRYL ALDEHYDES

摘要

The invention discloses simple and rapid method for the preparation of α-substituted acryl aldehydes. More particularly, the invention discloses a method for the preparation of α-substituted acryl aldehydes via a gold-catalysed [1,3] rearrangement of the allenyl ethers with a record turnover frequency of 4600 h−1 at 0.05 mol % of the catalyst concentration in homogeneous gold(I) catalysis. The α-substituted acryl aldehydes synthesized by the instant process are used as building blocks in organic synthesis.

主权项

1. A process for the preparation of α-substituted acryl aldehydes of Formula 2wherein n represents 0,1
“A” is selected from the group consisting of phenyl; benzyl; substituted or unsubstituted furyl, thiophenyl, pyrrolyl, pyridyl, benzofuryl, benzothiophenyl, indolyl, wherein substituents are selected from N—(C1-C4)alkyl or N-arylalkyl; R is selected from the group consisting of hydrogen, aryl, arylalkyl, (C1-C6) linear or branched alkyl; R1, R2 and R3 are similar or different and independently selected from the group consisting of hydrogen, (C1-C4)alkoxy, N—(R4)2, where R4 is (C1-C6)alkyl; with a proviso when n is 0, then “A” is selected from the group consisting of benzocyclohexyl and ferrocenyl; comprising subjecting allenyl ethers of Formula 1 to Au(I) complex catalysed [1, 3] O→C rearrangement to obtain α-substituted acryl aldehydes of Formula 2 with turnover frequency of 4600 h−1.