| Abstrakt: |
Palladium-catalyzed cross-coupling reaction of α-phosphonovinyl nonafluorobutanesulfonates (nonaflates) 1 with dialkyl phosphites gave versatile intermediate reagents, gembis(phosphono)ethylenes 2a-d in 35-93% yields. The reaction of bis(diethylphosphono)ethylene (2a) with tribromomethyllithium to give the Michael adduct 3 was followed by treatment with potassium hydride to form l,1-dibromo-2,2-bis(phosphono)cyclopropane 4 in 68% yield. The reaction of 2a with [N-(p-toluenesulfonyl)- or N-(methanesulfonyl)imino]phenyliodinane produced the corresponding 1-sulfonyl-2,2-bis(phosphono)aziridines 5a,b in 54-75% yields. Treatment of 2a with sodium or potassium imidazole and a halogenating agent led to [1-halo-2-( 1 -imidazolyl)ethyl]-1,1-bis-phosphonates 7a,b (halogen = Cl,F) in 73-47% yields. Similar reaction using 3-lithiopyridine and a halogenating agent afforded [1-halo-2-(3-pyridyl)ethyl)]-1,1-bisphosphonates 8a,b in 83-85% yields. [ABSTRACT FROM AUTHOR] |
