Silicon assisted diversified reaction of a β-silylmethylene malonate with dimethylsulfoxonium methylide
作者:Pintu K. Kundu、Rekha Singh、Sunil K. Ghosh
DOI:10.1016/j.jorganchem.2008.11.005
日期:2009.2
Reaction of dimethylsulfoxoniummethylide with a β-silylmethylene malonate gives diversified products, cyclopropane, cyclobutane or allyl and homoallyl silanes depending upon the stoichiometry of the reactants and reaction conditions. Contrary to this, reaction of a β-arylmethylene malonate gives only the cyclopropane product. The product(s) formed are unique and the silicon group played a crucial
Programmed Sequential Additions to Halogenated Mucononitriles
作者:Adam J. Zahara、Elsa M. Hinds、Andrew L. Nguyen、Sidney M. Wilkerson-Hill
DOI:10.1021/acs.orglett.0c03007
日期:2020.10.16
synthesized from 2,1,3-benzothiadiazole and undergo conjugate addition/elimination reactions with both nitrogen (40–95% yield) and carbon nucleophiles (72–93% yield). Secondary amines undergo monosubstitutions, while carbon nucleophiles are added twice. The sequence of addition of the nucleophiles could be controlled to give mixed addition products. The multicomponent coupling products could then be
Unnatural α-amino ethyl esters from diethyl malonate or ethyl β-bromo-α-hydroxyiminocarboxylate
作者:Eloi P Coutant、Vincent Hervin、Glwadys Gagnot、Candice Ford、Racha Baatallah、Yves L Janin
DOI:10.3762/bjoc.14.264
日期:——
We have explored here the scope of the age-old diethyl malonate-based accesses to α-aminoesters involving Knoevenagel condensations of diethyl malonate on aldehydes, reductions of the resulting alkylidenemalonates, the preparation of the corresponding α-hydroxyimino esters and their final reduction. This synthetic pathway turned out to be general although some unexpected limitations were encountered
Chiral-Zn(NTf<sub>2</sub>)<sub>2</sub>-Complex-Catalyzed Diastereo- and Enantioselective Direct Conjugate Addition of Arylacetonitriles to Alkylidene Malonates
Chiral N,N′‐dioxide/Zn(NTf2)2 complexes were demonstrated to be highly effective in the direct asymmetricconjugateaddition of arylacetonitriles to alkylidene malonates under mild conditions. A wide range of substrates were tolerated to afford their corresponding products in moderate‐to‐good yields with high diastereoselectivities (82:18–>99:1 d.r.) and enantioselectivities (81–99 % ee). The reactions