Synthesis and absolute configuration of the insecticidal sesquilignan (+)-HAEDOXAN a in honour of professor G. H. Neil Towers 75th birthday
摘要:
The insecticidal neolignan, (+)-haedoxan A, was synthesized from (S)-(+)-beta-vinyl-gamma-butyrolactone and (2R,3R)-(+)-6-formyl-7-methoxy-3-methoxymethyl-2-(3,4-methylenedioxyphenyl)-1,4-benzodioxane, and its absolute configuration was unequivocally established as 1S,2R,5R,6S,2"R,3''R. (C) 1998 Elsevier Science Ltd. All rights reserved.
Synthesis and absolute configuration of the insecticidal sesquilignan (+)-HAEDOXAN a in honour of professor G. H. Neil Towers 75th birthday
摘要:
The insecticidal neolignan, (+)-haedoxan A, was synthesized from (S)-(+)-beta-vinyl-gamma-butyrolactone and (2R,3R)-(+)-6-formyl-7-methoxy-3-methoxymethyl-2-(3,4-methylenedioxyphenyl)-1,4-benzodioxane, and its absolute configuration was unequivocally established as 1S,2R,5R,6S,2"R,3''R. (C) 1998 Elsevier Science Ltd. All rights reserved.
β-alkyl substituted γ-lactones and whiskey lactone analogues were synthesized, and the odor properties were evaluated. During the preparation of the chiral intermediates, we found good reaction conditions for the highly enantioselective esterification of 3-arylmethyl-2-methyl-1-propanols to kinetically resolve them. The results of the olfactoryevaluations of the synthesized lactones revealed that the alkyl
Process for the preparation of (S)-4-fluoromethyl-dihydro-furan-2-one useful in the preparation of the DPP-IV inhibitor (S)-1 ((2S,3S,11bS)-2-amino-9,10-dimethoxy-1,3,4,6,7, 11b-hexahydro-2h-pyrido[2,1-a] isoquinolin-3-yl)-4-fluoromethyl-pyrrolidin-2-one
申请人:Abrecht Stefan
公开号:US20060270853A1
公开(公告)日:2006-11-30
This invention relates to a process of the preparation of the novel intermediate (S)-4-fluoromethyl-dihydro-furan-2-one of the formula
and with its use for the manufacture of pyrido[2,1-a]isoquinoline derivatives of the formula
which are useful for the treatment and/or prophylaxis of diseases which are associated with DPP IV.
The spatial arrangement of groups within a chiral ligand is essential for its catalytic performance. This work describes convenient synthesis of (R,Sp)-1-(2-(diphenylphosphano)ferrocenyl)-1-(2-diphenylphosphanophenyl)-N,N-dimethylmethanamine, a diastereomer of the well known (R,Rp)-Taniaphos ligand. The compound was prepared from the same homochiral amine as Taniaphos by sequential twofold lithiation
A significant improvement in enantioselectivity has been achieved in the 1,4-additions of diethylzinc to 2-cyclopentenone, 2-cyclohexenone and 5,6-hydro-2H-pyran-2-one (up to 93%, 98% and 94% ee, respectively) by using a chiral diphosphite-copper catalyst under suitable reaction conditions. (C) 2004 Elsevier Ltd. All rights reserved.
Ferrocene phosphane–carbene ligands in Cu-catalyzed enantioselective 1,4-additions of Grignard reagents to α,β-unsaturated carbonyl compounds
Chiral ferrocene phosphane-carbenes are good ligands for the copper-catalyzed 1,4-addition of Grignard reagents to various Michael acceptors. The products were obtained in high enantiomeric purity (up to e.r. = 95:5) and excellent regioselectivity (r.r. = 99:1). These ligands are also useful for domino conjugate addition followed by enolate trapping with imine and aldehyde. (C) 2013 Elsevier B.V. All rights reserved.