Gheorghe Ruxandra, Chamoreau Lise-Marie, Kapitan Josef, Ovanesyan Nikolaï S, Aldoshin Sergei M, Hecht Lutz, Barron Laurence D, Train Cyrille, Gruselle Michel
Laboratoire de Chimie Inorganique et Matériaux Moléculaires, UMR-CNRS 7071, IFR 2769,Université Pierre et Marie Curie-Paris 6, F-75252 Paris Cedex 05, France.
Chirality. 2008 Nov;20(10):1085-91. doi: 10.1002/chir.20577.
A pair of enantiomerically pure quaternary ammonium salts with a chiral side chain, methyl-(R)-(1-methylpropyl)di(n-propyl)ammonium iodide 1 and methyl-(S)-(1-methylpropyl)di(n-propyl)ammonium iodide 2, and the related racemate, methyl-(rac)-(1-methylpropyl)di(n-propyl)ammonium iodide 3, were synthesized through a reductive alkylation procedure, starting from enantiomerically pure and, also, racemic forms of (rac)-(1-methylpropyl)amine. A spectroscopic chiroptical signature in solution was provided by the Raman optical activity spectra of compounds 1 and 2. The crystallographic structures of 1, 2, and 3 were examined by single crystal X-ray diffraction. 1 crystallizes in the tetragonal space group P4(3)2(1)2 (no. 96), a = b = 12.826 (2) A, c = 17.730 (2) A, V = 2916.9 (5) A(3), Z = 8, Flack coefficient 0.04 (2). 2 crystallizes in the tetragonal space group P4(1)2(1)2 (no. 92), a = b = 12.842 (1) A, c = 17.749 (2) A, V = 2927.0 (5) A(3), Z = 8, Flack coefficient 0.05 (2). The crystal structures and space groups for 1 and 2 are enantiomorphs and the crystallographic investigation confirmed the absolute configuration of the stereocenter in both compounds. 3 crystallizes in the monoclinic space group P2(1)/n(no. 14), a = 8.178 (1) A, b = 14.309 (2) A, c = 12.328 (2) A, beta = 96.811 (6) degrees, V = 1432.4 (2) A(3), Z = 4.
通过还原烷基化方法，从对映体纯的以及外消旋形式的(rac)-(1-甲基丙基)胺出发，合成了一对具有手性侧链的对映体纯季铵盐，即甲基-(R)-(1-甲基丙基)二(n-丙基)碘化铵1和甲基-(S)-(1-甲基丙基)二(n-丙基)碘化铵2，以及相关的外消旋体甲基-(rac)-(1-甲基丙基)二(n-丙基)碘化铵3。化合物1和2的拉曼光学活性光谱提供了溶液中的光谱手性特征。通过单晶X射线衍射研究了1、2和3的晶体结构。1结晶于四方晶系空间群P4(3)2(1)2（编号96），a = b = 12.826(2) Å，c = 17.730(2) Å，V = 2916.9(5) ų，Z = 8，弗拉克系数0.04(2)。2结晶于四方晶系空间群P4(1)2(1)2（编号92），a = b = 12.842(1) Å，c = 17.749(2) Å，V = 2927.0(5) ų，Z = 8，弗拉克系数0.05(2)。1和2的晶体结构和空间群是对映体，晶体学研究证实了两种化合物中立体中心的绝对构型。3结晶于单斜晶系空间群P2(1)/n（编号14），a = 8.178(1) Å，b = 14.309(2) Å，c = 12.328(2) Å，β = 96.811(6)°，V = 1432.4(2) ų，Z = 4。
