The structures of four para-substituted derivatives of diphenylethynylmethanol have been determined [ditolylethynylmethanol, di(4-chlorophenyl)ethynylmethanol, di(4-bromophenyl)ethynylmethanol and bis(4,4′-biphenylyl)ethynylmethanol]. The dimethyl, dichloro, dibromo and diphenyl compounds have been analysed using X-ray diffraction at 150 K, and the dichloro compound has also been studied using neutron diffraction at 150 K. In common with the parent diphenylethynylmethanol [Garcia, Ramos, Rodriguez & Fronczek (1995). Acta Cryst. C51, 2674–2676], all four derivatives fail to form the expected strong O—H...O hydrogen bonds due to steric hindrance. Instead, the supramolecular structural organization in this family of gem-alkynols is mediated by a variety of weaker interactions. The two most acidic protons, O—H and C[triple-bond]C—H, participate in weak hydrogen bonds to π-acceptors, forming synthons that stabilize all five structures. These primary interactions are reinforced by a variety of other weak hydrogen bonds involving C—H donors and the hydroxy-O as an acceptor, and by halogen...halogen interactions in the dichloro and dibromo compounds.
确定了四种对位取代的二苯基乙炔基甲醇衍生物[二羟甲基乙炔基甲醇、二(4-氯苯基)乙炔基甲醇、二(4-溴苯基)乙炔基甲醇和双(4,4′-联苯基)乙炔基甲醇]的结构。二甲基、二氯、二溴和二苯基化合物已在 150 K 下用 X 射线衍射法进行了分析,二氯化合物也已在 150 K 下用中子衍射法进行了研究。与母体二苯基乙炔基甲醇[Garcia, Ramos, Rodriguez & Fronczek (1995). Acta Cryst. C51, 2674-2676]一样,由于立体阻碍,所有四种衍生物都未能形成预期的强 O-H...O 氢键。相反,这个 gem-alkynols 家族的超分子结构组织是由各种较弱的相互作用介导的。两个酸性最强的质子(O-H 和 C[三键]C-H)参与了与π受体的弱氢键作用,形成了能稳定所有五种结构的合子。C-H 给体与作为受体的羟基-O 之间的各种其他弱氢键,以及二氯和二溴化合物中的卤素......卤素相互作用,加强了这些主要相互作用。