Spectroscopic and structural evidence for the hydrogen bond nature of CC-H...C=C contacts in ethynyl steroids
Spectroscopic and structural evidence for the hydrogen bond nature of CC-H...C=C contacts in ethynyl steroids
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DOI：
10.1016/s0022-2860(97)00267-6
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发表时间：
1998-01-01
影响因子：
3.8
通讯作者：
Steiner, T
中科院分区：
文献类型：
--
作者：
Lutz, B;Kanters, JA;Steiner, T
结构和红外光谱证据表明，末端炔与C=C双键的直接接触具有弱氢键的基本特征。接触点指向α键的中心，而不是单个C原子之一。从H到C=C键中心的接触距离通常为2.8埃，最短距离类似于2.5埃。这种相互作用具有明显的长程性质，即使在很长的H…π距离约为3.0埃。所用样品主要由属于孕激素家族的乙炔基类固醇组成。(C)1998年Elsevier Science B.V.
Structural and IR-spectroscopic evidence is given that directed contacts from terminal alkynes to C=C double bonds possess the essential characteristics of weak hydrogen bonds. The contacts are directed at the center of the a-bond rather than at one of the individual C-atoms. The contact distances from H to the center of the C=C bond are typically 2.8 Angstrom, with the shortest distances being similar to 2.5 Angstrom. The interaction is of pronounced long-range nature and can be detected in the infrared spectrum even with a long H...pi distance of almost 3.0 Angstrom. The sample used is mainly composed of ethynyl steroids belonging to the progestine family. (C) 1998 Elsevier Science B.V.