Inter- and intramolecular Mitsunobu reaction based approaches to 2-substituted chromans and chroman-4-ones
摘要:
Two approaches to optically active 2-substituted chromans and chrornan-4-ones are described. The first utilized an intermolecular Mitsunobu reaction of a homochiral halopropanol and 2-bromophenol followed by cyclization to the 2-substituted chroman. In addition, a double lithiation procedure was developed to introduce additional functionality to the chroman. The second approach utilized an intramolecular Mitsunobu cyclization to give the 2-substituted chroman-4-one nucleus. The methodologies were applied to the syntheses of several biologically active natural and synthetic products. (c) 2005 Elsevier Ltd. All rights reserved.
A stereocontrolled route to 2-substituted chromans
作者:Kevin J Hodgetts
DOI:10.1016/s0040-4039(00)01530-6
日期:2000.10
A two-step synthesis of 2-substituted chromans of high enantiomeric purity is described. Mitsunobu reaction of homochiral halopropanols 10 with 2-bromophenol (9), followed by treatment with n-butyllithium under Parham cycloalkylation conditions generates 2-substituted chromans 7. The methodology was applied to the synthesis of the natural product tephrowatsin E (5) and the antiviral BW683C (6).
Inter- and intramolecular Mitsunobu reaction based approaches to 2-substituted chromans and chroman-4-ones
作者:Kevin J. Hodgetts
DOI:10.1016/j.tet.2005.04.047
日期:2005.7
Two approaches to optically active 2-substituted chromans and chrornan-4-ones are described. The first utilized an intermolecular Mitsunobu reaction of a homochiral halopropanol and 2-bromophenol followed by cyclization to the 2-substituted chroman. In addition, a double lithiation procedure was developed to introduce additional functionality to the chroman. The second approach utilized an intramolecular Mitsunobu cyclization to give the 2-substituted chroman-4-one nucleus. The methodologies were applied to the syntheses of several biologically active natural and synthetic products. (c) 2005 Elsevier Ltd. All rights reserved.