SYNTHESIS AND REACTIVITY OF 2-IODOPHOSPHININES

With the aim of synthesizing novel functionalized derivatives of phosp hinine (phosphabenzene), we investigated Diels-Alder approaches to 2-i odophosphinines. The precursor Cl2P-CHI2 reacted with triethylamine in the presence of 1,3-butadiene or its 2,3-dimethyl derivative to furni sh 2-iodophosphinines 6 which, directly or after formation of their pe ntacarbonyltungsten complexes, underwent a number of interesting funct ionalization reactions. Useful for reaction with a number of electroph iles were the organozinc reagent 4,5-dimethyl-2-iodozincophosphinine ( 9) which could be obtained directly from the corresponding 2-iodophosp hinine 6b and zinc either in DMF or in THF/TMEDA, and the pentacarbony ltungsten coordinated 2-lithio derivative 18.