作者:Zofia Meissner、Maria Chrzanowska
DOI:10.1016/j.tetasy.2015.01.002
日期:2015.2
The enantiospecific synthesis of (S)-(-)-8-oxoxylopinine 1 was performed using a lateral metallation strategy, in which (S)-alaninol or (S)-phenylalaninol was applied as chiral auxiliary and building block. (4S)-3-(4,5-Dimethoxy-2-methylbenzoy1)-2,2,4-trimethyl-1,3-oxazolidine 12 was synthesized starting from veratraldehyde 13. The addition reaction of benzylic anion generated in situ from chiral amide 12 into 6,7,-dimethoxy-3,4-dihydroisoquinoline 7a proceeded with simultaneous cyclization leading to the protoberberine alkaloid with high enantioselectivity. (C) 2015 Elsevier Ltd. All rights reserved.