20040-20-4Relevant articles and documents
Asymmetric Transfer Hydrogenation of 1,3-Alkoxy/Aryloxy Propanones Using Tethered Arene/Ru(II)/TsDPEN Complexes
Forshaw, Sam,Matthews, Alexander J.,Brown, Thomas J.,Diorazio, Louis J.,Williams, Luke,Wills, Martin
supporting information, p. 2789 - 2792 (2017/06/07)
A series of propanones containing combinations of aryloxy and alkoxy substituents at the 1- and 3-positions were reduced to the alcohols via asymmetric transfer hydrogenation using a tethered Ru(II)/TsDPEN catalyst. The enantioselectivities of the reductions reveal a complex pattern of electronic and steric effects which, when used in a matched combination, can lead to the formation of products of up to 68% ee (84:16 er) from this highly challenging class of substrate.
2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2- diazaphosphorine supported on polystyrene (PS-BEMP) as an efficient recoverable and reusable catalyst for the phenolysis of epoxides under solvent-free conditions
Zvagulis, Artis,Bonollo, Simona,Lanari, Daniela,Pizzo, Ferdinando,Vaccaro, Luigi
supporting information; scheme or table, p. 2489 - 2496 (2010/12/29)
2-tert-Butylimino-2-diethylamino-1,3-dimethylperhydro-1,3, 2-diazaphosphorine supported on polystyrene (PS-BEMP) is an efficient catalyst for the ring-opening of epoxides with phenols (1.0 equiv.). Excellent yields have been obtained and in most of the cases the final products have been isolated in pure form without any additional purification step. E-factors associated to this protocol are small and further improvements were obtained by setting a cyclic continuous-flow reactor operating under solvent-free conditions (SolFC) that allowed us to minimize waste and reduce the E-factor by 95% compared to batch conditions. In addition the representative synthesis of a 2,3-dihydrobenzo[1,4]dioxepin-5-one has been realized. Optimization of this process was achieved by setting up an automated multi-step continuous-flow reactor based on a phenolysis process and a subsequent lactonization by thermal treatment of the reaction mixture. 3-Phenoxymethyl-2,3-dihydrobenzo[e][1,4] dioxepin-5-one was isolated in pure form and on a multi-gram scale in a very satisfactory 86% overall yield and an E-factor of 1.47.
Highly regioselective ring opening of epoxides with polymer supported phenoxide and naphthoxide anions
Tamami,Iranpoor,Rezaei
, p. 2789 - 2795 (2007/10/03)
Amberlite IRA-400 supported phenoxide and naphthoxide anions are easily prepared. These polymer supported reagents that are highly air stable are used for the regioselective ring opening reactions of different epoxides to give aryl ether alcohols in high yields under mild reaction conditions.
