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Updated: Jun 3, 2026

Hydrolysis of a Ni-Schiff-Base Complex Using Conditions Suitable for Retention of Acid-labile Protecting Groups
Published on: April 6, 2017
Protecting-group-free synthesis of chokols
Carmen Pérez Morales1, Julieta Catalán, Victoriano Domingo
1Department of Organic Chemistry, University of Granada, Avda. Fuentenueva, 18071 Granada, Spain.
Abstract:
As a result of a combined theoretical and experimental study, we describe a two-step protocol for the preparation of an optically pure, multifunctional, cyclopentanic core shared by a number of natural products. This process is based on a hitherto unreported Ti(III)-mediated diastereoselective cyclization in which the hydroxy-directed template effect played by the Ti(III) species was found to be crucial for the stereoselective outcome of the reaction. The viability of this concept was confirmed with the first protecting-group free synthesis of three enantiopure chokols, namely, chokols K, E, and B.
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