Silphos [PCl3−n(SiO2)n]: a heterogeneous phosphine reagent for formylation and acetylation of alcohols and amines with ethyl formate and acetate

[PVP‐SO3H] HSO4: An Efficient Polymeric Solid Acid Catalyst for the Formylation and N‐Boc Protection Reactions

“…Also, formamides employed as the major protecting groups of amines in peptide synthesis because the deprotection process can selectively take place in the presence of acetate or other ester protective groups . There are different methods for the protection of amines and alcohols in the form of formylation in the presence of various catalysts such as TiO 2 ‐P 25 , γ‐Fe 2 O 3 @HAp‐SO 3 H, HCOONa, CO 2 and Ph 2 SiH 2 , CO 2 /PhSiH 3 /TBAF, Silica sulfuric acid, HClO 4 –SiO 2 , Al (HSO 4 ) 3 and Silphos [PCl 3 ‐nSiO 2 ) n ] …”

Vilsmeier–Haack reagent-promoted formyloxylation of α-chloro-N-arylacetamides by formamide

“…9 α-Haloketones are also reported formyloxylated by formamides in the presence of copper catalyst 10 or Silphos agent [PCl 3 -n (SiO 2 ) n ]. 11 However, the scopes of the reactions are limited, no other α-halocarbonyl compound including amides and esters is reported. In our development of Vilsmeier-Haack reagent for the synthesis of heterocyclic compounds and performing functional group transformations, 12 we serendipitously found that the reagent was possible to active the α-halo group in the amide functionality toward nucleophilic substitution.…”

Silica-bonded N-propyl sulfamic acid as an efficient catalyst for the formylation and acetylation of alcohols and amines under heterogeneous conditions

“…Further, if the alcoholic group is planned to be oxidized later in the synthetic scheme, the formylated alcoholic group need not be deprotected and direct oxidation under Oppenauer conditions can be realized. [8][9][10][11] Although various formylating agents have been reported previously, there are still serious limitations for the preparation of formates due to the drastic reaction conditions, the use of uncommon reagents, formation of undesirable or toxic by-products, the application of expensive catalysts for preparation of formylating agents, and thermal instability of the reagents. 12 To the best of our knowledge, one of the most common formylating agents is formic acid which is corrosive and toxic.…”