一些富勒烯C60双加成物稳定性的理论研究

Ｃ6 0 具有 30个等同的可参与化学反应的活泼双键 ,制备并表征富勒烯多加成产物是富勒烯化学中最前沿的课题之一 .Ｈｉｒｓｃｈ等15 ]通过研究Ｃ6 0 亚甲基加成反应 ,提出了双加成物立体选择性的一般规律 .我们在Ｃ6 0 氧加成方面做了类似的研究工作6 8].本文选取几类富勒烯环双加成衍生物即富勒烯氧化产物Ｃ6 0 Ｏ2 6 ]( 1 )、富勒烯含氮衍生物Ｃ6 0 (ＮＨ) 2 5 ]( 2 )、富勒烯含吡咯环衍生物Ｃ6 0 (ＣＨ2 ＮＨＣＨ2 ) 2 9]( 3)和富勒醇前体Ｃ6 0 (ＳＯ4) 2 10 ]( 4)作为模型分子进行理论研究 ,以探寻富勒烯多加成反应的一般性规律 .…

Theoretical Studies on the Stabilities of Some C60 Bis-adducts

The quantum chemical investigations of some representative bis-adducts of C₆₀, C₆₀O₂, C₆₀(NH)₂, C₆₀(CH₂NHCH₂)₂ and C₆₀(SO₄)₂ have been carried out at the AM1 and PM3 semi-empirical molecular orbital levels. The relative energies of various isomers of these C₆₀ bis-adducts have been calculated. For C₆₀O₂ and C₆₀(NH)₂ with the sterically non-demanding addends, cis-1 isomer resulted from 1,2-additions to adjacent 6/6 ring fusion is the lowest energy structure; for C₆₀(CH₂NHCH₂)₂ and C₆₀(SO₄)₂ with sterically demanding addends, the most energetically preferred structure is e isomer. This is consistent with and enhances the general rule for regio-selectivity of fullerene C₆₀ established by Hirsch, though Hirschs rule is summarized on the basis of methanofullerenes. The thermodynamic analysis is not significant to explain the experimentally observed regiochemistry for C₆₀ bis-adducts, and the kinetic reasons or mechanisms may dominant in determining the regioselectivity of fullerene bis-adducts. Further addition patterns for multiple addition were also discussed.