Sood Paul, Koutha Mohan, Fan Maomian, Klichko Yaroslav, Zhang Hongming, Lattman Michael
Department of Chemistry, Southern Methodist University, Dallas, Texas 75275-0314, USA.
Inorg Chem. 2004 May 3;43(9):2975-80. doi: 10.1021/ic035359d.
New calix[5]arene trivalent phosphorus derivatives have been synthesized which should be excellent ligands with which to study and control the interaction of a ligand atom with a metal. The larger cavity of the calix[5]arene (compared to calix[4]arene) provides a good balance between constraint and flexibility. Treatment of p-tert-butylcalix[5]arene with 2 equiv of either tris(dimethylamino)phosphine or dichlorophenylphosphine inserts two RP moieties into the calix[5]arene framework to give calix52(OH) (1, R = Me2N; 2, R = Ph). Further treatment of 1 with 4 equiv of HCl gives calix52(OH) (3). Heating a solution of the monophosphorus compound calix5(OH)3 (4) releases dimethylamine to yield both monomeric calix5(OH)2 (6) and dimeric calix5(OH)2 (7), the latter having a tubelike geometry. X-ray crystallographic studies confirm the structures and show that 1 and 2 have approximate cone conformations while 3 has an approximate 1,2-alternate conformation. The orientations of the phosphorus lone pairs and oxygen atoms in all derivatives provide a framework for both soft and hard ligand interactions within the calix[5]arene.
新型杯[5]芳烃三价磷衍生物已被合成出来，它们应是用于研究和控制配体原子与金属相互作用的优异配体。杯[5]芳烃（与杯[4]芳烃相比）的较大空腔在限制和灵活性之间提供了良好的平衡。用2当量的三（二甲基氨基）膦或二氯苯基膦处理对叔丁基杯[5]芳烃，将两个RP部分插入杯[5]芳烃骨架中，得到杯52(OH)（1，R = Me2N；2，R = Ph）。用4当量的HCl进一步处理1得到杯52(OH)（3）。加热单磷化合物杯5(OH)3（4）的溶液会释放二甲胺，生成单体杯5(OH)2（6）和二聚体[杯5(OH)2]2（7），后者具有管状结构。X射线晶体学研究证实了这些结构，并表明1和2具有近似的锥型构象，而3具有近似的1,2-交替构象。所有衍生物中磷孤对电子和氧原子的取向为杯[5]芳烃内的软配体和硬配体相互作用提供了一个框架。
