The gas phase reaction of fluoride(1-) and hydroxide(1-) ions with alkyl formates

Fragmentation reactions of some aliphatic esters in the NCl(F−) and NCl(NH2−) mass spectra

“…Hence, there must be a second mechanism giving rise to the carboxylate ions. Riveros et al 10,18 have suggested that this is the sN2 reaction (5a, b). However, a sN2 reaction with backside attack of the nucleophile at the a-carbon atom of the ester alkoxy group is not possible in the 1-adamantyl ester 7 for steric reasons.…”

Gas-phase ionic reactions of benzyl and methoxide anions

“…Charge-localized ions reacted to give mainly ␣-elimination, whereas chargedelocalized ions reacted exclusively at the carbonyl group. Pioneering work by Riveros and co-workers 15,16 on alkyl formate reactions with alkoxides and by Johlman and Wilkins 17 on hydroxide-alkyl formate systems showed that when different pathways are available, ␣-elimination is a major pathway. Brickhouse and Squires 6 have also shown that there are significant differences in the reactivity of charge localized and delocalized ions with 6,6-dimethylfulvene.…”

“…Although the Riveros reaction, equation (1), is the major reaction pathway for methoxide, 11,15,16 Table 1 shows that in the reaction between benzyl anion and various formates, no S N 2 or Riveros reaction products were observed. For ethyl and especially tert-butyl formate, we observe secondary Riveros reaction products:…”

“…transacylation, are of major importance in organic synthesis and in biological systems and have been studied extensively in condensed-and gas-phase studies. 5,[10][11][12][13][14][15] At least some of the comparisons between localized and delocalized ions can be made more effectively if the thermodynamics of the reactions are comparable. Previous studies 5 focused on the allyl ion, which is more basic than the methoxide ion.…”

Hydrolysis and retro‐aldol cleavage of ethyl threo‐2‐(1‐adamantyl)‐3‐hydroxybutyrate: competing reactions

“…The hydrolysis of carboxylic acid esters (RCOOR') is one of the most fundamental and thoroughly studied chemical reactions 1–9. A variety of experimental and theoretical studies10–55 on ester hydrolysis have provided critical insights into the fundamental reaction mechanism. Besides extensive interests within chemistry, the mechanism of base‐catalyzed hydrolysis of esters figures prominently in many biological processes,6–9, 56, 57 such as the metabolism of the neurotransmitter acetylcholine and the degradation of cocaine.…”