Mechanism of the gold(L)-catalyzed Rautenstrauch rearrangement: A center-to-helix-to-center chirality transfer

作者:Faza ON; Lopez CS; Alvarez R; de Lera AR*
来源:Journal of the American Chemical Society, 2006, 128(7): 2434-2437.
DOI:10.1021/ja057127e

摘要

The mechanism of the stereospecific gold (I)-catalyzed Rautenstrauch rearrangement of (E)-1- ethynyl-2-methyl-but-2-en-yl acetate to 3,4-dimethyl-cyclopent-2-enone has been computationally addressed using DFT (B3LYP/6-31G*, SDD for Au). Our results indicate that the bond formation event follows the Au(I)-induced acetyl transfer to the vicinal alkyne and that it is the helicity of the pentadienyl cation intermediate which keeps memory of the chiral information. The fidelity of the center-to-helix-to-center chirality transfer requires that the rates of helix interconversion and pivaloyl rotation are slower than the cyclization, as calculations predict.

  • 出版日期2006-2-22