A new cyclam-based ligand, 1,4,8,11-tetraazacyclotetradecane-1,4-bis(methylphosphonic acid) (1,4-H4te2p), was synthesized. Cyclam was protected by the reaction with PhP(S)Cl2 to form exclusively five-membered cyclic phenylphosphonothioic diamide 2 in a moderate yield. The solid-state structures of 2 and several by-products were determined. Compound 2 was isolated as two stable conformers differing in a mutual position of benzene ring and sulfur atom with respect to the cyclam ring. Compound 2 was used for the synthesis of 1,4-dibenzylcyclam. However, the deprotection of the thiophosphoryl-protected bis(methylphosphonate diester) with aqueous HCl under non-optimized conditions led to a mixture of cyclam derivatives differently substituted with methylphosphonic acid groups. The crystal structures of the target product, 1,4-H4te2p, and also 1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetrakis(methylphosphonic acid) (H8tetp) were determined. A similar reaction with cyclen (1,4,7,10-tetraazacyclododecane) led only to hardly purifiable mixtures.
合成了一种新的基于环戊烯的配体,1,4,8,11-四氮杂环四十二烷-1,4-双(甲基膦酸)酯(1,4-H4te2p)。环戊烯通过与PhP(S)Cl2反应保护,以中等收率形成仅含5元环苯基磷酸硫酰胺2。确定了2和几种副产物的固态结构。化合物2以两种稳定构象分离,其苯环和硫原子与环戊烯环相对位置不同。化合物2用于合成1,4-二苯基环戊烯。但是,在非优化条件下使用水溶HCl去保护硫磷酸双(甲基膦酸酯)导致了不同取代甲基膦酸基的环戊烯衍生物混合物。确定了目标产物1,4-H4te2p和1,4,8,11-四氮杂环四十二烷-1,4,8,11-四(甲基膦酸)酯(H8tpt)的晶体结构。与环六胺(1,4,7,10-四氮杂环十二烷)的类似反应仅导致难以纯化的混合物。