Nucleophilic Acyl Substitutions of Anhydrides with Protic Nucleophiles Catalyzed by Amphoteric, Oxomolybdenum Species.

Abstract

Substitution reactions Substitution reactions O 0040Nucleophilic Acyl Substitutions of Anhydrides with Protic Nucleophiles Catalyzed by Amphoteric, Oxomolybdenum Species. -A mild and efficient approach to a wide range of esters, amides, and thioesters starting from anhydrides is developed. Various substrates including cyclic and mixed ones react successfully as well as chemoselectively. -(CHEN*, C.-T.; KUO, J.-H.; PAWAR, V. D.; MUNOT, Y. S.; WENG, S.-S.; KU, C.-H.; LIU, C.-Y.; J.

High Valent Oxo-molybdenum Complexes as Efficient Catalysts for C-X Bond Forming Reactions

“…Chen and co-workers have demonstrated that the oxo-molybdenum complexes MoO 2 Cl 2 (1) and MoOCl 4 (118) are very efficient catalysts for the construction of C-O, C-N, and C-S bonds by nucleophilic acyl substitution (NAS) of anhydrides with a myriad array of alcohols, amines, and thiols, affording the corresponding acylated derivatives in high yields and high chemoselectivity (Fig. 47) [36]. Besides acetic anhydride, the catalytic system is amenable to a diverse array of cyclic and acyclic, aliphatic and aromatic anhydrides.…”

Development of hydrophilic photolabile hydroxyl protecting groups

“…Conjugate addition of 17 to methyl acrylate led to 19. acetylation with acetic anhydride catalyzed by MoCl 2 O 2 converted the trityl alcohols 18, 19, and 8 to the corresponding PPG reagents 20, 21, and 22, respectively. 10 The neutral protecting group installation protocol developed in our laboratory 7 was successfully generalized to the new reagents. Thus, without using any other chemical reagents, heating the trityl acetates and an alcohol R′OH at 120 °C resulted in 7, 11, and 12, respectively.…”