The reaction of the dianionic intermediate [resulting from the reductive opening of phthalan (1) with lithium] with chiral N-tert-butylsulfinyl aldimines 3 in the presence of ZnMe2 gives, after hydrolysis, N-tert-butylsulfinyl amino alcohols 4 with high diastereoselectivity. Successive treatment of compounds 4 with hydrogen chloride in methanol, thionyl chloride in chloroform and sodium hydroxide yields 3-substituted tetrahydroisoquinolines 6. (C) 2009 Elsevier Ltd. All rights reserved.
Reductive Ring-Opening of Phthalan and Isochroman: Application to the Stereoselective Synthesis of Tetrahydroisoquinolines and Tetrahydrobenzazepines
作者:Daniel García、Francisco Foubelo、Miguel Yus
DOI:10.1002/ejoc.201000111
日期:2010.5
The reaction of the dianionic intermediates 2a,b resulting from the lithiation of phthalan (1a) and isochroman (1b) with chiral N-tert-butylsulfinyl aldimines 9 in the presence of ZnMe2 gave, after hydrolysis, N-tert-butylsulfinyl amino alcohols 10 and 13, respectively, with high diastereoselectivity. Successive treatment of compounds 10 and 13 with hydrogen chloride in methanol, thionyl chloride in