Synthesis of the rac-6-hydroxy-3-methoxycyclohex-2-enone and resolution through recrystallization of its diastereomeric N-tosyl-(S)-proline esters
✍ Scribed by V.G. Zaitsev; D.G. Sachava; G.S. Yankovskaya; N.I. Garbuz
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- English
- Weight
- 116 KB
- Volume
- 12
- Category
- Article
- ISSN
- 0899-0042
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✦ Synopsis
The synthesis and resolution of rac-6-hydroxy-3-methoxycyclohex-2-enone, by fractional crystallization of diastereomeric esters of N-protected (S)-proline was shown to be an effective method for preparation of both pure diastereomers (>95% d.e., according to (1)H NMR data). The absolute configuration of the asymmetric center in cyclohexene ring was determined based on the inversed octant rule for the sign of circular dichroism for these cyclohexenones (n-pi*-transition band at approximately 300 nm) and further substantiated by chemical conversion of the (-)-(6R,2'S)-diastereomer into the known (+)-(R)-4-hydroxycyclohex-2-enone. Copyright 2000 Wiley-Liss, Inc.