Synfacts 2007(8): 0870-0870  
DOI: 10.1055/s-2007-968752
Organo- and Biocatalysis
© Georg Thieme Verlag Stuttgart · New York

Organocatalytic Friedel-Crafts Reactions of Naphthols and Nitroolefins

Contributor(s): Benjamin List, Subhas Chandra Pan
T.-Y. Liu, H.-L. Cui, Q. Chai, J. Long, B.-J. Li, Y. Wu, L.-S. Ding, Y.-C. Chen*
chengdu Institute of Biology and Sichuan University, Chengdu, P. R. of China
Further Information

Publication History

Publication Date:
24 July 2007 (online)

Significance

The authors report an asymmetric Michael-type Friedel-Crafts alkylation of naphthols and nitroolefins. Bifunctional thiourea catalysts were found to be effective for this reaction and catalyst 1 proved optimal. With 20 mol% of catalyst 1 moderate to good yields (69-83%) and high enantioselectivities (er = 93:7 to 97:3) were obtained for different β-naphthols with different nitroolefins. The authors have observed an unexpected cascade reaction to dimeric 1,2-dihydronaphtho[2,1-b]furanyl-2-hydroxylamine derivatives after prolonging the reaction time, and excellent enantioselectivity (er = 99.5:0.5) was attained.