A new access to various functionalised trimethylsilyl substituted carbo- and heterocycles
摘要:
Trimethylsilyl substituted carbo- and heterocycles could be efficiently prepared using a ring closing metathesis reaction of the corresponding silylated dienes. (C) 2002 Elsevier Science Ltd. All rights reserved.
A new access to various functionalised trimethylsilyl substituted carbo- and heterocycles
摘要:
Trimethylsilyl substituted carbo- and heterocycles could be efficiently prepared using a ring closing metathesis reaction of the corresponding silylated dienes. (C) 2002 Elsevier Science Ltd. All rights reserved.
Removable Silyl Group as a “Masked Proton” in Oxy-2-oxonia(azonia)-Cope Rearrangement: Applications in Stereoselective Total Synthesis of Natural Macrolides
In the presence of a Lewis acid, trimethylsilyl-substituted β,γ-unsaturated ketones and aldehydes (imines) undergo nucleophilic addition to produce zwitterionic intermediates, followed by oxy-2-oxonia(azonia)-Cope rearrangements to give homoallylic esters (amides). In the case of TMS-containing 2-vinylcycloalkanones, the process results in ring-enlargement, providing 10- to 16-membered lactones. This