Highly efficient and chemoselective acetalization and thioacetalization of aldehydes catalyzed by propylphosphonic anhydride (®T3P) at room temperature

Ethyl‐2‐cyano‐2‐(2‐nitrophenylsulfonyloximino)acetate (ortho‐ NosylOXY) Mediated Acetalization and Thioacetalization of Aldehydes

“…The involvement of o ‐NosylOXY for the synthesis of acetals could be illustrated by the following plausible mechanism based on the existing literature . Alcohol ( 1 ) reacts with an aldehyde ( 2 ) and o ‐NosylOXY ( 3 ), which results in the formation of oxocarbenium ion ( 6 ) through intermediate ( 5 ) releasing Oxyma anion and 2‐nitrobenzenesulphonic acid.…”

“…Furthermore, Vijaykumar and his colleagues reported a well‐known peptide coupling reagent T3P mediated chemoselective acetalization/thioacetalization of aldehydes in the presence of ketone at room temperature with a catalytic amount of the reagent . Zhu et al.…”

Cascade reaction engineering on zirconia-supported mesoporous MFI zeolites with tunable Lewis–Brønsted acid sites: a case of the one-pot conversion of furfural to γ-valerolactone

“…FDA was synthesized from furfural via acetalization via two 2-propanol molecules. As reported previously, [37][38][39][40] the acetalization is normally carried out with strong Brønsted mineral acids (e.g. HCl or H 2 SO 4 ) or solid Brønsted acids (e.g., Amberlyst 70 or Naon-H).…”

Propanephosphonic Acid Anhydride (T3P®) - A Benign Reagent for Diverse Applications Inclusive of Large-Scale Synthesis

“…A chemoselective reaction of aldehydes 254 and alcohols or thiols using a catalytic amount of T3P (10 mol%) under mild conditions to produce acetals or thioacetals (Scheme 66) was developed. 71 The protocol was advantageous as it tolerated acid-sensitive functionalities. Aromatic aldehydes with electrondonating or -withdrawing substituents, and aliphatic and sterically hindered aldehydes were converted into the corresponding acetals or thioacetals 255-257.…”

“…The chemoselectivity of the reaction was elucidated by the transition-state energies of aldehydes and ketones based on quantum mechanical calculations using density functional theory. 71 The less flexible methyl analogue of T3P, methylcyclophosphonic anhydride (MCPA; 260), was employed to compare the energies of intermediates 261 and 262 with those of the starting materials for both the aldehydes and the corresponding methyl ketones (Scheme 68). In all cases, the formation of the acetal intermediate 261 was found to be more favored than that of the corresponding ketal 262 by several kilocalories per mole, owing to the steric crowding offered by the substituents.…”