New Phosphorus-Carbon Cage Compounds by Diels-Alder and Homo Diels-Alder Reactions of 1,3,5-Triphosphabenzenes with Alkenes

摘要

Ethylene, various monosubstituted alkenes (acrylic acid derivatives, styrene), as well as some selected disubstituted alkenes (maleic acid derivatives, fumaric acid derivatives, nor-bornene, cyclopentadiene) undergo Diels-Alder reactions with the 1,3,5-triphosphabenzenes 1 under mild conditions to furnish the dihydrotriphosphabarrelenes 9, 11a-c, 13a-e, 15a-d, 17a,b, and 24. The monoadduct 26 as well as the diad-ducts 27 and 28 are isolated following the reaction with norbornadiene. Cyclopropene is the only alkene to undergo a Diels-Alder/homo Diels-Alder reaction sequence to afford the hexacyclic system 20.