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The Stereochemical Course of the ?-Hydroxyphosphonate-Phosphate Rearrangement.

ABSTRACT: The phosphonate-phosphate rearrangement is an isomerisation of ?-hydroxyphosphonates bearing electron-withdrawing substituents at the ?-carbon atom. We studied the stereochemical course of this rearrangement with respect to phosphorus. A set of four diastereomeric ?-hydroxyphosphonates was prepared by a Pudovik reaction from two diastereomeric cyclic phosphites. The hydroxyphosphonates were separated and rearranged with Et3 N as base. In analogy to trichlorphon, which was the first reported compound undergoing this rearrangement. All four hydroxyphosphonates could be rearranged to 2,2-dichlorovinyl phosphates. Single-crystal X-ray structure analyses of the ?-hydroxyphosphonates and the corresponding phosphates allowed us to show that the rearrangement proceeds with retention of configuration on the phosphorus atom.

SUBMITTER: Pallitsch K

PROVIDER: S-EPMC4515106 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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The Stereochemical Course of the α-Hydroxyphosphonate-Phosphate Rearrangement.

Pallitsch Katharina K Roller Alexander A Hammerschmidt Friedrich F

Chemistry (Weinheim an der Bergstrasse, Germany) 20150608 28

The phosphonate-phosphate rearrangement is an isomerisation of α-hydroxyphosphonates bearing electron-withdrawing substituents at the α-carbon atom. We studied the stereochemical course of this rearrangement with respect to phosphorus. A set of four diastereomeric α-hydroxyphosphonates was prepared by a Pudovik reaction from two diastereomeric cyclic phosphites. The hydroxyphosphonates were separated and rearranged with Et3 N as base. In analogy to trichlorphon, which was the first reported comp ...[more]

PMID: 26059025

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