131832-07-0Relevant articles and documents
Molecular Recognition and Stereoselectivity: Geometrical Requirements for the Multiple Hydrogen-Bonding Interaction of Diols with a Multidentate Polyhydroxy Macrocycle
Kikuchi, Yasuaki,Kato, Yasushi,Tanaka, Yasutaka,Toi, Hiroo,Aoyama, Yasuhiro
, p. 1349 - 1354 (1991)
Resorcinol-dodecanal cyclotetramer 1 in CDCl3 forms hydrogen-bonded, 1/1 complexes with cyclohexanediols as well as with 2,4-pentane- and 2,5-hexanediol as their open-chain analogues and cyclohexanol and cis- and trans-4-tert-butylcyclohexanol.The affinities to 1 of cyclic diols (K=(1.1-10) * 102 M-1 at 25 deg C) are significantly larger than those of open-chain diols (36-43 M-1) and monools (8-11 M-1).Those of regio- and stereoisomers of cyclohexanediol depend on the configuration (axial-equatorial > diequatorial) and relative positions (1,4 >> 1,2 > 1,3) of the two OH groups involved and decrease in the order cis-1,4 (K=1.04 * 103) > cis-1,2 (2.64 * 102) > trans-1,3 (1.81 * 102) > trans-1,4 (1.29 * 102) > cis-1,3 (1.24 * 102) > trans-1,2 (1.06 * 102 M-1); the stereoselectivities are thus cis-1,4/trans-1,4 = 8.0, cis-1,2/trans-1,2 = 2.5, and trans-1,3/cis-1,3 = 1.5.The selectivities in the diol binding are discussed in terms of multiple hydrogen bonding of diol and 1.The relatively large binding constant (K) for cis-1,4-diol with one axial and one equatorial OH group is attributed to an effective and simultaneous two-point hydrogen bonding of the two OH groups with two adjacent binding sites of 1 as a multidentate host.