Modification of regioselectivity in cycloadditions to C70 under microwave irradiation

被引：74

作者：

Langa, F ^{[1
]}

de la Cruz, P

de la Hoz, A

Espíldora, E

Cossío, FP

Lecea, B

机构：

[1] Univ Castilla La Mancha, Fac Ciencias Medio Ambiente, Toledo 45071, Spain

[2] Univ Basque Country, Fac Farm, Vitoria 01080, Spain

[3] Univ Castilla La Mancha, Fac Quim, E-13071 Ciudad Real, Spain

[4] Univ Basque Country, Fac Quim, E-20080 San Sebastian, Spain

来源：

JOURNAL OF ORGANIC CHEMISTRY | 2000年 / 65卷 / 08期

关键词：

D O I：

10.1021/jo991710u

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The regioselectivity of the cycloaddition of N-methylazomethine ylide to C-70 can be modified by using microwave irradiation as the source of energy. Under microwave irradiation and by choosing the appropriate solvent and irradiation power, the 5-6 isomer is the major product, a situation that is in contrast to conventional heating where the 1-2 isomer predominates. Moreover, isomer 7-21, which represents 13% of monoadducts under classical heating, is not formed under microwave irradiation and with ODCB as solvent. Theoretical calculations predict an asynchronous mechanism and suggest that the modification of the regiochemical outcome is related to the relative energies and hardnesses of the transition structures involved.

引用

页码：2499 / 2507

页数：9

共 72 条

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