反式-1,2-双[5-取代苯基(口恶)唑-2-基]-乙烯的构象

The Conformation of trans-1,2-Bis[5-(substituted phenyl)-oxazol-2-yl]ethylene

合成了反式-1,2-双[5-(2,4,6-三甲基苯基)(口恶)唑-2-基]乙烯(1_a),并用分子力学法(MMX程序)计算了标题化合物(POEOP,2,5-二甲基-POEOP及2,4,6-三甲基POEOP).POEOP的结构、构象与X衍射结果颇吻合,分子中2个(口恶)唑环呈稳定的反向排布.比同向排布稳定4.6kJ/mol,旋转能垒约16.8～20.9 kJ/mol.还讨论了标题系列化合物的构象对其紫外光谱的影响.

Trans-1,2-bis[5-(2,4,6-trimethylphenyl)oxazol-2-yl]ethylene has been synthesized.The calculation of molecular mechanic force field (MMX program) for POEOP,2,5-dirnethyl-POEOP and 2,4,6-trimethyl-POEOP has been performed.The structural parameters of POEOP determined consist with the MMX calculation.Both two oxazole ring moieties are arranged in an-ti conformation which is stable than the syn one by 4.6 kJ/mol and the rotation energy barrier is ca.lculation 20.9 kj/mol.Besides,the relationship between the conformation and UV spectra of POEOP system has been discussed.