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Synthesis of a Key Building Block for a Butyrolactone → 1,3‐Diol Approach to the Polyol Part of Roflamycoin
Author(s) -
MuñozTorrero Diego,
Brückner Reinhard
Publication year - 1998
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/(sici)1099-0690(199806)1998:6<1031::aid-ejoc1031>3.0.co;2-d
Subject(s) - chemistry , lactone , diol , ozonolysis , polyol , stereochemistry , ring (chemistry) , organic chemistry , polyurethane
For preparing tris(γ‐lactone) 3 the mono(γ‐lactone) 6 was synthesized from the dichlorodiol 12 (99.8% ee ). Bisepoxide 9 – derived from dichlorodiol 12 (99.8% ee ) – was ring‐opened with the Gilman cuprate from 2‐lithio‐1,5‐hexadiene and CuI giving almost exclusively the monoepoxide 21 ; in five more steps, γ‐lactone 30 with the same stereotriad as the target molecule 6 but a different protecting group was obtained. Monoepoxide 33 – also derived from dichlorodiol 12 – was ring‐opened with the same Gilman cuprate affording compound 35 . It was transformed into the correctly protected γ‐lactone 6 in seven steps, key reactions being the ozonolysis 35 → 36 and the diastereoselective reduction 36 → anti ‐ 37 .