A Convenient Synthesis of 1,1-Disubstituted 1,2,3,4-Tetrahydroisoquinolines via Pictet-Spengler Reaction Using Titanium(IV) Isopropoxide and Acetic-Formic Anhydride.
作者:Yoshie Horiguchi、Hirokazu Kodama、Masayoshi Nakamura、Tsuyoshi Yoshimura、Kaori Hanezi、Hiroko Hamada、Toshiaki Saitoh、Takehiro Sano
DOI:10.1248/cpb.50.253
日期:——
A synthesis of 1,1-disubstituted 1,2,3,4-tetrahydroisoquinolines (6) was achieved in a highly efficient manner via Pictet-Spengler reaction of arylethylamines (1) and acyclic and cyclic ketones (2) using titanium (IV) isopropoxide and acetic-formic anhydride. The cyclization of the in situ formed acyliminium ion (4) to N-formyl 1,2,3,4-tetrahydroisoquinoline (5) was greatly facilitated by using trifluoroacetic
通过使用钛(IV)的芳基乙胺(1)与无环和环状酮(2)的Pictet-Spengler反应以高效方式合成了1,1-二取代的1,2,3,4-四氢异喹啉(6)异丙醇和乙酸甲酸酐。通过使用三氟乙酸作为附加试剂,可以极大地促进原位形成的酰基酰亚胺离子(4)环化为N-甲酰基1,2,3,4-四氢异喹啉(5)。通过一锅法进行Pictet-Spengler反应,为制备各种1,2,3,4-四氢异喹啉提供了一种方便有效的方法。