Synthesis of enantiomerically pure. gamma.-(menthyloxy) butenolides and (R)-and (S)-2-methyl-1, 4-butanediol

…, B De Lange, JC De Jong

Index: Feringa, Ben L.; Lange, Ben de; Jong, Johannes C. de Journal of Organic Chemistry, 1989 , vol. 54, # 10 p. 2471 - 2475

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Citation Number: 100

Abstract

a mixture of diastereomers 4a and 5a (6040 ratio) 7b by heating 5-hydroxy-2 (5H)-furanone (l)@ with 1.5 equiv of I-menthol.'O Enantiomerically pure 4a7b was obtained after two crystallizations of the mixture of 4a and 5a from petroleum ether. In a similar way the enantiomer of lactone 4, with the S configuration at the acetal carbon, was obtained starting with d-menthol as a chiral auxiliary (Scheme I). 1o The absolute configuration at the acetal ...