One-pot synthesis of stable phosphonium ylides using 2-mercaptopyrimidine derivatives

X‐ray structural analysis and theoretical studies of new phosphite‐derived ylides

“…As can be seen from Table 3, the difference between the relative stability of the E-4d and Z-4d isomer is not considerably high; for this reason, the isomers should undergo a rapid interchange. In addition, the partial double bond character in the two E and Z geometrical isomers in phosphorus ylide containing trialkyl phosphite (recent work) is weaker than phosphorus ylides involving triphenylphosphine (previous work [8][9][10][11][12][13][14][15]). Phosphites show a greater π -acidity compared to phosphines, and therefore the resonance form, in which the electron pair is located on the carbonyl oxygen (betainic resonance form), is less favored.…”

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].…”

Synthesis of Stable Carbamate Phosphorus Ylides by a Four-Component Reaction And Dynamic 1H-Nmr Study of the Energy Barriers for the Rotation around the Carbon–Nitrogen Single Bond and the Carbon–Carbon Double Bond

“…Although the mechanism of this reaction has not been experimentally established, a proposed mechanism for this reaction is shown on the base of the literature [5][6][7][8][9][10][11][18][19][20][21][22][23] in Scheme 3.…”