Organophosphorus Compounds, Part 146* Imidovanadium(V) Complexes as Reaction Partners for Kinetically Stabilized Phosphaalkynes. Synthesis and Reactivity of 3-Aza-l,2,4,6-tetraphospha-quadricyclanes
The Lewis base adducts of imidovanadium(V) compounds 5a,b undergo chemoselective cyclooligomerization reactions with the kineticallystabilizedphosphaalkynes 4a-e to furnish the azatetraphosphaquadricyclanes 6a-f with incorporation of the imido fragment. The reactivity of this novel class of heteropolycyclic compounds has been examined exemplarily for compound 6a. Complexation of one and two phosphorus
Organophosphorus Compounds, Part 153; New Phosphorus-Carbon Cage Compounds by Diels - Alder and Homo Diels - Alder Reactions of 1,3,5-Triphosphabenzenes with Alkynes
Eleven new phosphorus-carbon cagecompounds 3a-d, 5a-e, 7, and 8 have been synthesized in mostly excellent yields by reactions of the 1,3,5-triphosphabenzenes 1 with acetylene, several monosubstituted acetylenes, and cyclooctyne. While most of the alkynes react with the heterobenzenes 1 in a sequence of Diels-Alder and homo Diels-Alder reactions to furnish the cage-compounds 3a-d, 5a-e, and 7 with
Phenylnitrile oxide as well as mesitylnitrile oxide underwent 1,3-dipolar cycloaddition reactions with the 1,3,5-triphosphinines 2 under mild conditions to furnish the condensed heterocyclic compounds 9 and 11, respectively. Oxadiphospholes 14 were accessible by fragmentation reactions of 11.
Imidovanadium(V) Complexes as Reaction Partners for Kinetically Stabilized Phosphaalkynes: Synthesis of 1,2,4-Azaphosphavanada(V)-cyclobutenes, 1,3,5-Triphosphabenzenes, and 1H-1,2,4-Azadiphospholes
Cycloaddition reactions of the kinetically stabilized phosphaalkynes 1 with the imidovanadium(v) trihalides 9 furnish the 1,2,4-azaphosphavanada(v)cyclobutenes 10. The stability of these novel metallacyclic compounds depends solely on the substitutents of the imido unit. Thus, the imidovanadium(v) species 9 with tertiary alkyl groups on the N atom form stable addition products with 1 while in the cases