Thwartingβ-Hydride Elimination: Capture of the Alkylpalladium Intermediate of an Asymmetric Intramolecular Heck Reaction
- 17 April 2001
- journal article
- research article
- Published by Wiley in Angewandte Chemie International Edition in English
- Vol. 40 (8) , 1439-1442
- https://doi.org/10.1002/1521-3773(20010417)40:8<1439::aid-anie1439>3.0.co;2-f
Abstract
In spite of containing three conformationally accessible β -H atoms, palladacycle 1 a is an isolable intermediate in the asymmetric Heck cyclization of 2 a. Although 1 a is stable in the presence of the hydrotriflate salt of 1,2,2,6,6-pentamethylpiperidine, it is converted into the oxindole Heck product when exposed to the more acidic hydrotriflate salt of 2,6-di-tert-butylpyridine. Heck cyclization of 2 b is also believed to proceed by way of a palladacyclic intermediate 1 b, which in this case undergoes β-methoxide elimination. Bn=benzyl.This publication has 26 references indexed in Scilit:
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