Wittig-Horner Reaction of Dimethyl Phthalide-3-phosphonates with Ketones: Synthesis of 3-Ylidenephthalides and Their Conversion to 2,2-Disubstituted Indan-1,3-diones Including Spirocyclic Compounds
A Tandem Claisen-Decarboxylation-Aldol Reaction – Facile Access to The Fredericamycin A Core
作者:Sundarababu Baskaran、Edgar Nagy、Manfred Braun
DOI:10.1002/jlac.199719970206
日期:1997.2
A tandemreaction of doubly deprotonated indanecarboxylic acid 3 with ethoxyphthalide 5 leads to the formation of the spirocyclic diastereomers 6a and the 6b in a ratio of 9:1. They are converted to the spirodiketone core 2 of fredericamycin A (1).