Selective synthesis of 2‐(5‐oxo‐1‐arylhex‐1‐yn‐3‐yl)phenyl benzoates via FeCl
<sub>3</sub>
‐mediated cascade reactions of propargylamines with
<i>β</i>
‐enamino ketones
A mild and efficient FeCl3‐mediated cascade reaction of ortho‐hydroxyl propargylamines with β‐enamino ketones has been developed. This protocol provided a practical and selective method to synthesize 2‐(5‐oxo‐1‐arylhex‐1‐yn‐3‐yl)phenyl benzoates via in situ generated alkynyl o‐quinone methides following a cascade intermolecular 1,4‐conjugate addition/intramolecular nucleophilic addition/reverse Claisen
Acceleration of Petasis Reactions of Salicylaldehyde Derivatives with Molecular Sieves
作者:Xianglin Shi、Dominique Hebrault、Michael Humora、William F. Kiesman、Hairuo Peng、Tina Talreja、Zezhou Wang、Zhili Xin
DOI:10.1021/jo202117u
日期:2012.1.20
Mild reaction conditions for Petasis reactions of substituted salicylaldehydes with various amines and arylboronic acids in the presence of molecular sieves were developed. Molecular sieves (MS) significantly accelerated the reaction rates and drove the reactions to high conversions. The conditions were applied to the synthesis of the core structure of BIIB042, a gamma-secretase modulator, without stereochernical erosion of a stereogenic center in the salicylaldehyde intermediate.