Ruthenium-catalyzed tandem ring closing metathesis (RCM) – atom transfer radical cyclization (ATRC) sequences
作者:Bernd Schmidt、Michael Pohler
DOI:10.1016/j.jorganchem.2005.06.042
日期:2005.12
alpha-omega-Dienes bearing a pendant trichloroacetoxy group undergo a tandem RCM - radical cycloisomerization sequence leading to bicyclic gamma-butyrolactones, with both steps of the sequence being catalyzed by ruthenium. (c) 2005 Elsevier B.V. All rights reserved.
Catalyst economy. Part 2: Sequential metathesis—Kharasch sequences using the Grubbs metathesis catalysts
作者:Chris D. Edlin、James Faulkner、Peter Quayle
DOI:10.1016/j.tetlet.2005.12.018
日期:2006.2
Sequential ring-closing metathesis (RCM)–Kharasch cyclizations are promoted by the Grubbs metathesis catalysts and provide rapid access to bicyclic lactones and lactams.
monitored by (1)H and (3)(1)P NMR spectroscopies in order to understand the intimate details of the catalytic cycles. Polyhalogenated substrates and the ethylene released upon metathesis induced the clean transformation of catalystprecursor 1 into the Ru(II)-Ru(III) mixed-valence compound [(p-cymene)Ru(mu-Cl)(3)RuCl(2)(PCy(3))], which was found to be an efficient promoter for atomtransferradical reactions