Smith Graham, Wermuth Urs D
School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.
Acta Crystallogr C. 2010 Jan;66(Pt 1):o5-10. doi: 10.1107/S0108270109049154. Epub 2009 Dec 12.
The 1:1 proton-transfer compounds of L-tartaric acid with 3-aminopyridine [3-aminopyridinium hydrogen (2R,3R)-tartrate dihydrate, C(5)H(7)N(2)(+).C(4)H(5)O(6)(-).2H(2)O, (I)], pyridine-3-carboxylic acid (nicotinic acid) [anhydrous 3-carboxypyridinium hydrogen (2R,3R)-tartrate, C(6)H(6)NO(2)(+).C(4)H(5)O(6)(-), (II)] and pyridine-2-carboxylic acid [2-carboxypyridinium hydrogen (2R,3R)-tartrate monohydrate, C(6)H(6)NO(2)(+).C(4)H(5)O(6)(-).H(2)O, (III)] have been determined. In (I) and (II), there is a direct pyridinium-carboxyl N(+)-H...O hydrogen-bonding interaction, four-centred in (II), giving conjoint cyclic R(1)(2)(5) associations. In contrast, the N-H...O association in (III) is with a water O-atom acceptor, which provides links to separate tartrate anions through O(hydroxy) acceptors. All three compounds have the head-to-tail C(7) hydrogen-bonded chain substructures commonly associated with 1:1 proton-transfer hydrogen tartrate salts. These chains are extended into two-dimensional sheets which, in hydrates (I) and (III) additionally involve the solvent water molecules. Three-dimensional hydrogen-bonded structures are generated via crosslinking through the associative functional groups of the substituted pyridinium cations. In the sheet structure of (I), both water molecules act as donors and acceptors in interactions with separate carboxyl and hydroxy O-atom acceptors of the primary tartrate chains, closing conjoint cyclic R(4)(4)(8), R(3)(4)(11) and R(3)(3)(12) associations. Also, in (II) and (III) there are strong cation carboxyl-carboxyl O-H...O hydrogen bonds [O...O = 2.5387 (17) A in (II) and 2.441 (3) A in (III)], which in (II) form part of a cyclic R(2)(2)(6) inter-sheet association. This series of heteroaromatic Lewis base-hydrogen L-tartrate salts provides further examples of molecular assembly facilitated by the presence of the classical two-dimensional hydrogen-bonded hydrogen tartrate or hydrogen tartrate-water sheet substructures which are expanded into three-dimensional frameworks via peripheral cation bifunctional substituent-group crosslinking interactions.
已测定了L-酒石酸与3-氨基吡啶[3-氨基吡啶氢(2R,3R)-酒石酸盐二水合物，C(5)H(7)N(2)(+).C(4)H(5)O(6)(-).2H(2)O，(I)]、吡啶-3-羧酸（烟酸）[无水3-羧基吡啶氢(2R,3R)-酒石酸盐，C(6)H(6)NO(2)(+).C(4)H(5)O(6)(-)，(II)]和吡啶-2-羧酸[2-羧基吡啶氢(2R,3R)-酒石酸盐一水合物，C(6)H(6)NO(2)(+).C(4)H(5)O(6)(-).H(2)O，(III)]的1:1质子转移化合物。在(I)和(II)中，存在直接的吡啶鎓-羧基N(+)-H...O氢键相互作用，在(II)中为四中心的，形成联合的环状R(1)(2)(5)缔合。相比之下，(III)中的N-H...O缔合是与一个水O原子受体，该受体通过O(羟基)受体与单独的酒石酸根阴离子相连。所有三种化合物都具有通常与1:1质子转移氢酒石酸盐相关的头对尾C(7)氢键链亚结构。这些链扩展成二维片层，在水合物(I)和(III)中还涉及溶剂水分子。通过取代吡啶鎓阳离子的缔合官能团交联形成三维氢键结构。在(I)的片层结构中，两个水分子在与主酒石酸链的单独羧基和羟基O原子受体的相互作用中既作为供体又作为受体，形成联合的环状R(4)(4)(8)、R(3)(4)(11)和R(3)(3)(12)缔合。此外，在(II)和(III)中存在强的阳离子羧基-羧基O-H...O氢键[在(II)中O...O = 2.5387 (17) Å，在(III)中O...O = 2.441 (3) Å]，在(II)中它形成环状R(2)(2)(6)片层间缔合的一部分。这一系列杂芳族路易斯碱-氢L-酒石酸盐提供了分子组装的进一步实例，这种组装由经典的二维氢键氢酒石酸盐或氢酒石酸盐-水片层亚结构的存在促进，这些亚结构通过外围阳离子双官能取代基交联相互作用扩展成三维框架。
