One‐Pot Synthesis of Stable Phosphonium Ylides Using 2‐Aminothiophenol.

Abstract

Organo-phosphorus compoundsOrgano-phosphorus compounds S 0080 One-Pot Synthesis of Stable Phosphonium Ylides Using 2-Aminothiophenol. -Interestingly, coupling of DMAD and DEAD with PPh 3 and 2-aminothiophenol results in efficient formation of the desired ylides (IV), while starting from DIAD and the tert-butyl analogue (Vb) the corresponding ylides are not formed. -(ESMAILI*, A. A.; GHEREGHLOO, M.; ISLAMI, M. R.; BIJANZADEH, H. R.; Tetrahedron 59 (2003) 26, 4785-4788; Dep. Chem., Univ. Birjand, Birjand, Iran; Eng.) -Jannicke 42-176

Preparation of Stabilized Phosphorus Ylides via Multicomponent Reactions and Their Synthetic Applications

“…The reaction of some other strong SH-acids with DAAD in the presence of TPP leads to the corresponding phosphorane [210,211].…”

“…Dipotassium hydrogen phosphate and Magnesium oxide were found to catalyze the conversion of the stabilized phosphonium ylides (207) to compounds (208) 190] Protonation of the highly reactive 1:1 intermediates, produced in the reaction between (1) and (2), by 1-hydroxy-2-acetonaphthone (209) leads to vinyltriphenylphosphonium salts (210), which undergo aromatic electrophilic substitution reaction with the conjugate base of the phenol to produce dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-3-(triphenylphosphoranylidene) butanedioates (211). Silica gel was found to catalyze conversion of dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-3-(triphenylphosphoranylidene) butanedioates (211) to dialkyl 2-(3-acetyl-4-hydroxy-1-naphthyl)-2-butenedioates (212) in solvent-free systems under microwave and thermal conditions (Scheme 60) [191,192].…”