[4 + 2] Cycloaddition of Vinylphosphine Oxides to α-Oxy-o-xylylene as a route to Phosphorylated Naphthyl and Biaryl Scaffolds

Abstract

α-Oxy-o-xylylene, a highly reactive diene readily accessible from benzocyclobutenol, undergoes Diels–Alder reaction with vinylphosphine oxides, yielding the corresponding 2-phosphorylated 1-hydroxy-1,2,3,4-tetrahydronaphthalenes in excellent yields. Use of unsubstituted and trans-2-aryl-substituted vinylphosphine oxides leads to cycloadducts with complete regioselectivity and with cis/trans selectivity up to 19:1 in the most favorable case. In the case of P-stereogenic trans-2-aryl-substituted vinylphosphine oxides, a virtually complete chirality transfer from P to C can be achieved. Dehydration and aromatization of the obtained cycloadducts bearing the resolved P-stereogenic phosphinoyl groups can be carried out to afford the valuable P-stereogenic and axially chiral phosphorylated 1,2′-binaphthyl ring system. Cases of restricted rotation around Csp3–Csp2 single bond in some tetrahydronaphthalene cycloadducts have also been revealed.

Synthesis, Characterization and Application of a New Functionalized Polymeric Sorbent Based on Alkenylphoshine Oxide

“…With the necessary dibromide 4 in hand, we were able to complete our synthesis of 6 with 64% yield in the Heck reaction, using diphenylvinylphosphine oxide 5 and tris o-tollyl phosphine as a ligand [ 40 ]. The CyP(Ph)4-DVB obtained as a result of the crosslinking reaction of 1,2-bis(( E )-2-diphenylphospinoylethenyl)-cyclohex-1-ene with divinylbenzene was then applied as a potential polymeric sorbent for basic dye removal from aqueous solutions.…”