Cyclohexylbis(hydroxymethyl)phosphane: A Hydrophilic Phosphane Capable of Forming Novel Hydrogen‐Bonding Networks

Abstract

AbstractThe cyclohexyl‐substituted (hydroxymethyl)phosphane CyP(CH2OH)2 (1) has been prepared by reaction of the corresponding primary phosphane CyPH2 with aqueous formaldehyde. Compound 1 has been used as building block for the synthesis of new functionalized water‐soluble phosphorus compounds. Thus, Mannich‐type condensation of 1 with excess glycine affords the air‐stable amino acid phosphane conjugate CyP[CH2N(H)CH2COOH]2 (2). Simple oxidation of 1 with hydrogen peroxide and elemental sulfur leads to the crystalline chalcogenide derivatives CyP(O)(CH2OH)2 (3) and CyP(S)(CH2OH)2 (4). X‐ray diffraction analyses of the latter revealed distinct intermolecular hydrogen bonding motifs and possess different types of hydrogen bond networks to each other due to the different proton acceptor ability of the chalcogen atom X of the P=X group (X = O, S): while the oxygen atom of the P=O moiety in 3 serves as proton acceptor, affording a P=O–HO bifurcated network, the sulfur atom of the P=S group denies hydrogen bonding interactions. In addition, the ligand ability of 1 has been studied towards Pt(+2) and Cu(+1) ions: Reaction of 1 with Pt(COD)Cl2 (COD = cycloocta‐1,5‐diene) furnishes the air‐stable complex cis‐[PtCl2{CyP(CH2OH)2}2] (5), while the crystalline dimeric Cu(+1) complex [CuI{CyP(CH2OH)2}2]2 (6) results from the reaction of CuI with two molar equivalents of 1. The complex 6 shows a intermolecular hydrogen bonding pattern different from that of 1, 3 and 4, respectively. The new coordination compounds 5 and 6 represent metal‐phosphane labelled alcohols which are promising building blocks for the synthesis of metal‐based drugs. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)