118604-67-4Relevant articles and documents
New method for synthesizing (S)-metolachlor and its analogue
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Paragraph 0087-0090; 0091; 0092, (2020/03/12)
The invention relates to a new method for preparing (S)-metolachlor and its analogue. The (S)-metolachlor is taken as an example: the (S)-metolachlor is prepared from 2-methyl-6-ethylaniline and R-propylene glycol monomethyl ether through a four-step reaction. The method has the advantages of cheap and easily available raw materials, mild reaction conditions, high efficiency and very simple separation process.
Chiral Lewis base promoted trichlorosilane reduction of ketimines. An enantioselective organocatalytic synthesis of chiral amines
Guizzetti, Stefania,Benaglia, Maurizio,Cozzi, Franco,Annunziata, Rita
experimental part, p. 6354 - 6363 (2010/01/06)
The reduction of the carbon-nitrogen double bond is an important transformation. Here we report our studies on a family of chiral organic catalysts able to promote the stereoselective reduction of ketimines with trichlorosilane. The very cheap, metal-free catalysts were easily prepared in one step from commercially available products, namely a chiral aminoalcohol and picolinic acid derivatives. The catalyst structure was extensively modified in a study that allowed to identify an extremely active species, able to promote the reduction on a large variety of substrates with high efficiency (up to 95% ee). A three component methodology has been also developed, where the enantiomerically enriched amine was isolated after performing the reaction by mixing a ketone and an amine in the presence of trichlorosilane and the catalyst. Its synthetic potentiality was demonstrated by employing the present metal-free catalytic procedure in the preparation of (S)-metolachlor, a potent and widely used herbicide.
Chiral poisoning of rac-diop iridium complexes in the catalytic enantioselective hydrogenation of imines
Sablong, Rafael,Osborn, John A.,Faller
, p. 65 - 70 (2007/10/03)
Dimeric Ir(III) complexes [Ir(P-P)HI2]2 (P-P = enantiopure bisphosphine) have previously been shown to be efficient catalysts for the enantioselective hydrogenation of imines. In the present study we have prepared the analogues using