Reaction of hydroquinone with 2-ethoxyvinylphosphonyl dichloride

Synthesis of 1,2-oxaphosphinane 2-oxides and 1,2-oxaphosphinine 2-oxides: δ-phosphonolactones and δ-phosphinolactones

“…The acid-catalyzed reaction of (E)-( 2 93 The reactions could be conducted in dioxane at 60 1C for 25 h, leading to similar results. 94 The reaction of (E)-( 2 95 Benzene-1,4-diol also generated the corresponding bicyclic product in 78% yield under the catalysis of TFA in refluxing toluene for 3 h. 96 Similarly, the reaction of (E)-(2-ethoxyvinyl)phosphonic dichloride and naphthols produced both benzo-fused 12H-6,12-methanodibenzo[d,g][1,3,2]dioxaphosphocine 6-oxides and benzo[e][1,2]oxaphosphinine 2-oxides (Scheme 66). 97…”

“…However, benzene-1,4-diol formed bis(benzo[e][1,2]oxaphosphinine 2-oxide) 2,10-dihydroxy-12 H -6,12-methanodibenzo[ d , g ][1,3,2]dioxaphosph-ocine 6-oxide only in 78% yield (Scheme 65). 95 Benzene-1,4-diol also generated the corresponding bicyclic product in 78% yield under the catalysis of TFA in refluxing toluene for 3 h. 96…”