Reaction Between Isocyanides and Dialkyl Acetylenedicarboxylates in the Presence of Hydantoins – A One-pot Synthesis of Stable Ketenimines

Mechanochemical Preparation of 3,5-Disubstituted Hydantoins from Dipeptides and Unsymmetrical Ureas of Amino Acid Derivatives

“…N-alkylation with halogeno acetates and their derivatives, 14,7,15,16 and Michael addition 17 reactions, allowed the introduction of the carboxyalkyl group at the N-3 position of hydantoins, with a particular interest in phenytoin derivatives 3,[18][19][20]4,17 (Figure 1b). Miscellaneous procedures reported the reaction between acetylenic diesters and isocyanides, 21 or phosphates, 22 in the presence of an hydantoin molecule (Figure 1b). The rearrangement of Boc-protected dipeptide compounds, 23 diketopiperazines, 24 seven-membered cyclopeptides, 25 and oxazolidinones 26 were also described (Figure 1c).…”

In situ generation and protonation of the isocyanide/acetylene adduct: a powerful catalyst-free strategy for multicomponent synthesis of ketenimines, aza-dienes, and heterocycles

“…74,75 As shown in Fig. 9, reaction of NH-acids affords interesting ketenimines (123, 76 124, 77 125, 78 126, 79 127, 80 128, 81 129 and 130, 82 131, 83 132, 84 and 133 (ref. 74)), including sulfonamide, hydantoins, a-chlorocarbonyl, and active carbonyl skeletons.…”

A three-component synthesis of functionalized ketenimines by the reaction of alkyl isocyanides and dialkyl acetylenedicarboxylates in the presence of 2-quinolinol

“…9 The trapping of the 1:1 intermediate formed between dialkyl acetylenedicarboxylates and isocyanides with OH, NH, and CH acids has been widely studied. [10][11][12][13][14] In continuation of our interest in the application of isocyanides in multi-component reactions, MCR, [15][16][17][18] an efficient synthesis of ketenimine 4 from alkyl isocyanides 1 and dialkyl acetylenedicarboxylates 2 in the presence of a strong NH-acid, such as quinolin-2-ol, is reported herein. In some cases, minor amounts (13-25 %) of 1-azadienes 5 were obtained (Scheme 1).…”