Phosphoranes Formed From the Condensation of Trico-Ordinate Phosphorus Compounds With Phenanathraquinone

Phosphorus heterocycles from 2‐(2‐hydroxyphenyl)‐1H‐benzimidazole

“…The shift to higher frequencies of the N-Me 2 group and the small coupling constant [ 2 J ( 31 P, 13 C)] in phosphoranes 9 indicate that this group is in SCHEME 10 Synthesis of compounds 24. equatorial position. In phosphorane 24, the phenyl group is also in equatorial position as is deduced from its coupling constant P-Cipso [ 1 J ( 31 P, 13 C) = 189.9 Hz], characteristic for P(V) with an equatorial phenyl group [33,34]. Phenyl NMR data of phosphorane 24 are very similar to that of diphenylbicyclophosphorane, whose structure was determined by X-ray diffraction analyses [32].…”

“…In phosphorane 24, the phenyl group is also in equatorial position as is deduced from its coupling constant P-Cipso [ 1 J ( 31 P, 13 C) = 189.9 Hz], characteristic for P(V) with an equatorial phenyl group [33,34]. Phenyl NMR data of phosphorane 24 are very similar to that of diphenylbicyclophosphorane, whose structure was determined by X-ray diffraction analyses [32].…”

Reactions of α-Diketones ando-Quinones with Phosphorus Compounds

“…The condensation of tricoordinated phosphorus compounds 453 (X = O, S, NPh; R = Ph, Me, O-Xyl) with phenanthrenequinone leads to the formation of the phosphoranes 454 . , The structure of 454 (X = S, R = O-Xyl) was elucidated by X-ray crystallography …”

“…316 Also, the cyclic phosphite 443 reacts with phenanthrenequinone to form the phosphorane 444. 317 1,3,2-Dioxaphospholanes 445 (R 1 ) H, R 2 ) Me, R′ ) Cl, NCS; R 1 ) R 2 ) Me, CF 3 , R′ ) Cl, OMe, NMe 2 , OPh, SPh) react with o-chloranil in ether or boiling benzene to produce the corresponding spirophosphoranes 446. [318][319][320] The reaction of benzil and 3,5-di-tert-butyl-o-benzoquinone with 4,4-dimethyl-2-phenoxy-1,3,2-dioxaphospholane-5-one (447) yields the relative pentaoxaphosphoranes 448 and 449, respectively.…”

“…322 The condensation of tricoordinated phosphorus compounds 453 (X ) O, S, NPh; R ) Ph, Me, O-Xyl) with phenanthrenequinone leads to the formation of the phosphoranes 454. 317,323 The structure of 454 (X ) S, R ) O-Xyl) was elucidated by X-ray crystallography. 323 The chiral oxazaphospholidines 455 (R ) Ph, p-MeOC 6 H 4 ) react with R-diketones 17 (R 1 ) R 2 ) Me; R 1 ) R 2 ) Ph; R 1 ) Me, R 2 ) Ph) in dry pentane to form the corresponding spirophospholenes 456 as two diastereoisomers (A and B).…”