Categories: C-C Bond Formation > Oxygen-containing molecules > Carbonyl compounds >

Synthesis of acyloins (α-hydroxy carbonyl compounds)

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Recent Literature

Operationally simple cyanide-catalyzed silyl benzoin reactions afforded unsymmetrical aryl-, heteroaryl-, and alkyl-substituted silyl ether protected benzoin adducts with complete regiocontrol.
X. Linghu, J. S. Johnson, Angew. Chem. Int. Ed., 2003, 42, 2534-2536.

The development of a triazolium salt as an efficient precatalyst for the asymmetric benzoin condensation is described. The high asymmetric inductions in benzoin condensations are a result of the conformational rigidity of the bicyclic nucleophilic carbene catalyst and the shielding of the Breslow intermediate by the sterically demanding tert-butyl group.
D. Enders, U. Kallfass, Angew. Chem. Int. Ed., 2002, 41, 1743-1745.

An enantioselective intramolecular crossed-benzoin reaction catalyzed by novel chiral N-heterocyclic carbenes has been developed. A tetracyclic trazolium salt catalyzes the cyclization with generation of a quartenary stereocenter in high yields and excellent enantomeric excess.
D. Enders, O. Niemeier, T. Balensiefer, Angew. Chem. Int. Ed., 2006, 45, 1463-1467.

While 3,4;5,6-di-O-isopropylidene-N-phthaloyl-D-glucosamine propane-1,3-diyl dithioacetal underwent fast β-elimination, the corresponding N-acetyl derivative was easily deprotonated with butyllithium to form the dilithiated intermediate. Stoichiometry and temperature were crucial factors for selective C-C coupling with various electrophiles.
Y.-L. Chen, R. Leguijt, H. Redlich, R. Fröhlich, Synthesis, 2006, 4212-4218.