Fe(ClO₄)₃⋅xH₂O‐Catalysed Ritter Reaction: Synthesis of N‐tert‐Butyl Amides from Nitriles and Di‐tert‐Butyl Dicarbonate

Abstract

A convenient and excellent yield procedure for the synthesis of N-tert-butyl Amides by Ritter reaction with nitriles and (Boc) 2 O in the presence of Fe(ClO 4 ) 3 ⋅xH 2 O as a highly stable, effective and available catalyst is described. 2 3 4 5 6 7 8

Two different facile and efficient approaches for the synthesis of various N-arylacetamides via N-acetylation of arylamines and straightforward one-pot reductive acetylation of nitroarenes promoted by recyclable CuFe2O4 nanoparticles in water

“…Let A, A * denote a Leonard pair on V. We can determine whether A, A * is se By [13,Lemma 1.3] each eigenspace of A, A * has dimension one.…”

“…their extensive applications in various area such as peptide synthesis, agrochemicals, polymers, functional materials, dyes, fragrances and also existence in pharmaceuticals ( Figure 1) and natural products ( Figure 2) [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. Due to the importance of amide compounds, developing simple, practical, environmentally benign, cost-and time-effective manners for their synthesis is very valuable and necessary.…”

“…In the case of nitrobenzaldehydes and nitroacetophenones, the same behavior was observable. In which, the nitro group was reduced and acetylated to acetamide, however, the carbonyl moieties were reduced to alcoholic function without acetylation (Table 4, entries [10][11][12][13][14]. Molecules with the complexity of nitro and phenolic groups did not show any selectivity, and both of the functional groups were acetylated with the same reactivity.…”

A convenient synthesis of N-tert-butyl amides by the reaction of di-tert-butyl dicarbonate and nitriles catalyzed by Cu(OTf)2

“…In the Ritter reaction (Scheme 1d–h ), tert -butanol, 11,12 tert -butyl bromide, 13,14 tert -butyl acetate, 15–18 and tert -butyl benzoate 19 were employed with nitriles to produce N - tert -butyl amides. In addition to the above methods, methyl tert -butyl ethers, 20,21 methyl ethers, 22 and di- tert -butyl dicarbonate 23 can also be used to synthesize N - tert -butyl amides. In 2011, Kalkhambkar et al 14 produced N - tert -butyl amides from tert -butyl bromide and nitriles using 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM[PF 6 ])/NOPF 6 as the catalytic system (Scheme 1d ).…”

“…In the reactions listed above, only the reactions of nitriles with di- tert -butyl decarbonate were carried out at room temperature and excellent isolated yields of the products were obtained. In 2018, Feng et al 23 employed di- tert -butyl dicarbonate with nitriles in the presence of Fe(ClO 4 ) 3 · x H 2 O to form a series of N - tert -butyl amides (Scheme 1h ), but the catalyst was unstable and explosive. Therefore, it is necessary to find a mild and efficient catalyst for the synthesis of N - tert -butyl amides.…”