Quantum chemical characterization of the cyclization of the neocarzinostatin chromophore to the 1,5-didehydroindene biradical

被引：40

作者：

Cramer, CJ

Squires, RR

机构：

[1] Univ Minnesota, Dept Chem, Minneapolis, MN 55455 USA

[2] Univ Minnesota, Inst Supercomp, Minneapolis, MN 55455 USA

[3] Purdue Univ, Dept Chem, W Lafayette, IN 47907 USA

来源：

ORGANIC LETTERS | 1999年 / 1卷 / 02期

关键词：

D O I：

10.1021/ol990014d

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Quantum mechanical calculations have been carried out for the cyclization of the neocarzinostatin chromophore cyclonona-1,2,3,7-tetraen-5-yne to 1,5 didehydroindene. The 298 K reaction activation enthalpy, exothermicity, and singlet-triplet splitting (H-0) of the product biradical are predicted to be 17.8, 1.2, and -6.4 kcal/mol, respectively, at levels of theory showing near-quantitative agreement with experiment for the analogous cyclizations of hex-3-ene-1,5-diyne and hepta-1,2,4-trien-6-yne. Factors controlling differences in the Myers-Saito cyclization compared to the Bergman cyclization are analyzed.

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页码：215 / 218

页数：4

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