Slattery, CN;Clarke, LA;Ford, A;Maguire, AR

2013

January

Tetrahedron

Catalyst, additive and counterion effects on the efficiency and enantioselectivity of copper-catalysed C-H insertion reactions of alpha-diazosulfones

Validated

WOS: 17 ()

CYCLOPROPANATION REACTIONS DIAZOCARBONYL COMPOUNDS CARBENE INSERTION BONDS HYDROGENATION CYCLOPENTANE ESTERS HYDROVINYLATION CARBOXYLATES DERIVATIVES

69

1297

1301

Asymmetric copper-catalysed intramolecular C-H insertion reactions of alpha-diazosulfones in the presence of various group I salts are reported leading to substantial variation in reaction efficiencies and enantioselectivities. The borate additives NaBARF and KBARF were found to be the most effective additives for permitting highly enantioselective syntheses with short reactions times and high efficiency. Significantly, direct evidence of the critical role of the additive in enantioselective carbenoid reactions has been secured. (c) 2012 Elsevier Ltd. All rights reserved.

OXFORD

0040-4020

10.1016/j.tet.2012.12.003