Efficient Synthesis of Functionalized 2,5‐Dihydro‐1,2‐oxaphospholes.

Abstract

Organo-phosphorus compoundsOrgano-phosphorus compounds S 0080 Efficient Synthesis of Functionalized 2,5-Dihydro-1,2-oxaphospholes. -Stable title compounds (IV) and (VI) are obtained from the reaction of acetylenic carbonyl compounds (I), α-halo carbonyl compounds (II) and (V) and triphenylphosphine (III) under mild conditions. -(YAVARI*, I.; ALIZADEH, A.; ANARY-ABBASINEJAD, M.; Tetrahedron Lett. 44 (2003) 14, 2877-2879; Dep. Chem., Univ. Tarbiat Modarres, Tehran, Iran; Eng.) -Mais 27-158

An efficient domino one-pot synthesis of novel spirofuran-indenoquinoxalines by vinyltriphenylphosphonium salts

“…On the basis of the well-established chemistry of trivalent phosphorus nucleophiles, [40][41][42][43] it is reasonable to assume that spiro-1,2-oxaphospholes 7 results from the initial addition of triphenyphosphine 4 (1 mmol) to the acetylenic ester 5 (1 mmol) and subsequent attack of the resulting anion to the carbonyl carbon of the aromatic ketone 44 3 (1 mmol), which apparently cyclizes, in CH 2 Cl 2 at room temperature, to deliver the spiro-1,2-oxaphospholes 7. In the event we did not observe the expected MCR product 7; instead, the reaction afforded the corresponding methyl 4-methoxy a catalyst [45][46][47] in the reaction between the dimethyl acetylenedicarboxylate and 11H -indeno[1,2-b] quinoxalin-11-one 3a (Scheme 2).…”