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[1,5]-Anion relay via intramolecular proton transfer to generate 3,3-bis(silyl) allyloxy lithium: a useful scaffold for syn-addition to aldehydes and ketones. | LitMetric

[1,5]-Anion relay via intramolecular proton transfer to generate 3,3-bis(silyl) allyloxy lithium: a useful scaffold for syn-addition to aldehydes and ketones.

Org Lett

Key Laboratory of Drug-Targeting of Education Ministry and Department of Medicinal Chemistry, West China School of Pharmacy, ‡State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, P. R. China.

Published: February 2014

A [1,5]-anion relay has been achieved in 3,3-bis(silyl) benzyl enol ether. Deprotonation at the sterically more accessible benzyl position triggers an intramolecular proton transfer to generate the thermodynamically more stable 3,3-bis(silyl) allyloxy lithium. This endo-oriented allyl anion is stable at -78 °C and undergoes diastereoselective syn-addition at the γ-position with aldehydes and ketones to give monobenzyl-substituted 1,2-diols.

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Source
http://dx.doi.org/10.1021/ol4036402DOI Listing

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