Asymmetric addition of arylboronic acids to glyoxylate catalyzed by a ruthenium/Me-BIPAM complex.
نویسندگان
چکیده
The enantioselective synthesis of α-hydroxy esters by ruthenium-catalyzed 1,2-addition of arylboronic acids to tert-butyl glyoxylate is described. The use of RuCl(2)(PPh(3))(3) with (R,R)-Me-BIPAM gave optically active mandelic acids of up to 99% ee. Addition of a fluoride salt such as potassium fluoride (KF) or caesium fluoride (CsF) was effective for achieving high enantioselectivities.
منابع مشابه
Enantioselective addition of arylboronic acids to methyl 2-formylbenzoates by using a ruthenium/Me-BIPAM catalyst for synthesis of chiral 3-aryl-isobenzofuranones.
Ruthenium/Me-BIPAM-catalyzed asymmetric addition of arylboronic acids to methyl 2-formylbenzoates afforded chiral 3-aryl-isobenzofuranones. [RuCl2(p-cymene)]2/Me-BIPAM and RuCl2(PPh3)3/Me-BIPAM catalyst systems tolerate a variety of functional groups and give high yields with high enantioselectivities.
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An asymmetric palladium-catalyzed conjugate addition reaction of arylboronic acids to enone substrates was investigated mechanistically. Desorption electrospray ionization coupled to mass spectrometry was used to identify intermediates of the catalytic cycle and delineate differences in substrate reactivity. Our findings provide evidence for the catalytic cycle proceeding through formation of a...
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ورودعنوان ژورنال:
- Chemical communications
دوره 48 22 شماره
صفحات -
تاریخ انتشار 2012