36304-27-5Relevant academic research and scientific papers
ION PAIR CATALYSIS OF TUNGSTATE AND MOLYBDATE
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Page/Page column 34, (2017/10/30)
D The present invention relates to ion pair catalysts (I) comprising the cationic bisguanidinium ligand (A) and diperoxomolybdate anion (B). The present invention also relates to ion pair catalysts (III) comprising the cationic bisguanidinium ligand (C) and peroxotungstate anion (D). It further relates to the use of the said catalysts in the manufacture of enantiomerically enriched sulfoxides.
1,3-Cycloaddition of nitrile oxides to cyclic and open-chain 4-oxo-2- sulfinylbut-2-enoic acid derivatives
Garcia Ruano, Jose L.,Fraile, Alberto,Martin, M. Rosario
, p. 14491 - 14500 (2007/10/03)
The reactions of tert-butyl (E)-4,4-diethoxy-2-p-tolylsulfinylbut-2- enoate with benzonitrile, acetonitrile, and bromoformonitrile oxides yield isoxazoles. However, (S5,S(s))- and (R5,S(s))-5-ethoxy-3-p- tolylsulfinylfuranones with benzonitrile oxide afford isoxazolines. The reactivity of the double bond as a dipolarophile is strongly increased by the sulfinyl group. This is also the case of the regioselectivity, which usually is opposite to that exhibited by dipolarophiles lacking the sulfinyl group. Electrostatic interactions seemingly explain this behaviour. The π-facial selectivity of the reactions with the cyclic dipolarophiles is dependent on steric effects, but some role seems to be exerted by electrostatic attraction.
ASYMMETRIC MICHAEL ADDITIONS OF ESTER ENOLATES TO ENANTIOMERICALLY PURE VINYLIC SULFOXIDES SYNTHESIS OF 3-SUBSTITUTED GLUTARATE ESTERS IN HIGH ENANTIOMERIC PURITY
Posner, Gary H.,Weitzberg, Moshe,Hamill, Terence G.,Asirvatham, Edward,Cun-heng, He,Clardy, John
, p. 2919 - 2929 (2007/10/02)
Various ester enolate ions add as Michael donors to enantiomerically pure Michael acceptor cycloalkenone sulfoxides 1a and 1b and unsaturated lactone sulfoxides 3a and 3b.The level of asymmetric induction in some cases is extraordinarily high (>=95percent
