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Glycerol is the main side product in the biodiesel manufacturing process, and the development of glycerol valorization methods would indirectly contribute the sustainable biodiesel production and decarbonization. Transformation of glycerol to optically active C3 units would be one of the attractive routes for glycerol valorization. We herein present the asymmetric sulfonylative desymmetrization of glycerol by using a CuCN/( R , R )-PhBOX catalyst system to provide an optically active monosulfonylated glycerol in high efficiency. A high degree of enantioselectivity was achieved with a commercially available chiral ligand and an inexpensive carbonate base. The optically active monosulfonylated glycerol was successfully transformed into a C3 unit attached with differentially protected three hydroxy moieties. In addition, the synthetic utility of the present reaction was also demonstrated by the transformation of the monosulfonylated glycerol into an optically active synthetic ceramide, sphingolipid E.

Regio- and stereoselective installation of boryl and stannyl moieties into a carbon-carbon triple bond of various alkynes has been achieved based on a three-component coupling reaction by using a diboron and a tin alkoxide with the aid of a copper(II) acetate-tricyclohexylphosphine complex, giving diverse vic-borylstannylalkenes in a straightforward manner. Carbon-tin and carbon-boron bonds of the resulting borylstannylation product are successively transformed into carbon-carbon bonds by a Migita-Kosugi-Stille and a Suzuki-Miyaura coupling, leading to the formation of (Z)-tamoxifen with anti-breast cancer activity., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A copper complex has been found to catalyze the borylstannylation of alkenes through three-component coupling with a diboron and a tin alkoxide, affording vic-borylstannylalkanes of structural diversity in a regio- and stereoselective manner. The versatility of this borylstannylation has been also demonstrated by employing allenes, leading to the sole formation of borylstannylated products, which have alkenylborane and allylstannane units. [ABSTRACT FROM AUTHOR]

Formal hydroboration of internal alkynes proceeds regio- and stereoselectively by the use of a diboron reagent masked with 1,8-diaminonaphthalene (dan) in the presence of readily available [(Ph3P)3CuCl], leading to direct formation of diverse B-protected alkenylborons in high yield. The B(dan) moiety can also be efficiently installed into the CC double bond of alkenes to afford the respective alkylborons. [ABSTRACT FROM AUTHOR]

Regio- and stereoselective installation of boryl and stannyl moieties into a carbon-carbon triple bond of various alkynes has been achieved based on a three-component coupling reaction by using a diboron and a tin alkoxide with the aid of a copper(II) acetate-tricyclohexylphosphine complex, giving diverse vic-borylstannylalkenes in a straightforward manner. Carbon-tin and carbon-boron bonds of the resulting borylstannylation product are successively transformed into carbon-carbon bonds by a Migita-Kosugi-Stille and a Suzuki-Miyaura coupling, leading to the formation of ( Z)-tamoxifen with anti-breast cancer activity. [ABSTRACT FROM AUTHOR]