The Action of Ammonia on Benzoin

Abstract

The action of ammonia on benzoin has been studied previously by Laurent,1 Erdmann,2 and Japp and Wilson.3 These investigators found that the reaction leads to three products-amarone (C28H22N2, m.p. 245°)[also called benzoinimide (Erdmann) and ditolane-azotide (Japp and Wilson)], benzoinam (C28H23N2O, m.p. 190°-220°d epending on the rate SUMMARY 1. The action of ammonia on benzoin in boiling acetic acid yields amarone, dihydroamarone, and 2-methyl-4,5-diphenylglyoxaline.2. Desylamine is assumed to be an intermediate product in this reaction. It behaves like benzoin toward ammonia in acetic acid.3. In the presence of formic acid the formation of pyrazines is suppressed, the isolated products being iV-desylformamide and 4,5-diphenylglyoxaline.

Research on the reaction of furil with ammonium acetate

“…Their generated pathway was shown in Scheme 2. The results were in agreement with the published literature [18]. …”

Metal chloride hydrates as Lewis acid catalysts in multicomponent synthesis of 2,4,5-triarylimidazoles or 2,4,5-triaryloxazoles

“…The best results (higher than 80% yield) starting from benzil (4) Different mechanistic pathways have been proposed for this multicomponent reaction having the benzil or benzoin as starting materials. 15,28,33 The proposed rationale by Kokare et al 19 seems to be in accordance with the results in Table 1 (Scheme 2). The authors suggested the initial formation of N,N-ketal (9) under Brønsted acidic catalysis from benzaldehyde (6a) and 2 equivalents of NH 4 OAc (7).…”

“…By the proposed mechanistic pathway suggested by Davidson et al, 15 it is clear the aid of acetic acid as a Brønsted acid catalyst. Triaryloxazoles are structurally similar to triarylimidazoles and also have some of their properties, but have been less studied so far.…”

“…15 Intending to confirm this hypothesis, it was performed the reaction of benzoin (5, 2.0 mmol), NH 4 OAc (7, 4.0 mmol) under refluxing of ethanol and CeCl 3 . 7H 2 O (0.10 mmol) over 4 h in absence of the aldehyde.…”

Synthesis of α-Acyloxyketone Derivatives <i>via</i> the Platinum-Catalyzed Migration of Propargylic Esters

“…α-Acyloxyketone has also been used as a simple starting material for the stereoselective synthesis of a variety of different structures, including numerous 1,2-diols [4][5][6][7][8] and heterocyclic systems. [9][10][11] Based on the importance of α-acyloxyketones to chemistry, the development of a concise synthetic method for the preparation of α-acyloxyketone derivatives is important. Although a wide variety of synthetic methods have been investigated to date, 12,13) reports pertaining to the direct synthesis of α-acyloxyketone III by the oxidation of alkyne I are rare, most likely because of the difficulties associated with suppressing the over-oxidation of the product and controlling the regioselectivity of the reaction [14][15][16] (Chart 1).…”