Alkyne and amine

The coupling reactions of alkynes and aldehydes catalyzed by iron(III) salts have been discussed above (Scheme 10, routes B and C). The three-component coupling of aldehydes, alkynes, and amines is equivalent to the coupling reaction between alkynes and imines. Wang et al. reported such a three-component coupling catalyzed by FeCls in the absence of any ligand (Scheme 17) [33]. 

Scheme 17 Iron-catalyzed three-component coupling reactions of aldehydes, terminal alkynes, and amines...

Recently, the three-component couplings of a-oxyaldehydes, alkynes, and amines in water were investigated by using gold, silver, and copper... 

Table 9 Coupling of aldehydes, alkynes, and amines catalyzed by Agl in water...

Mononuclear complexes [U(C5Me5)2(NHR)2] (R = 2,6-dimethylphenyl, Et, or Bu) have been synthesized and structurally characterized. It was shown that in the presence of terminal alkynes and amines these complexes catalyze the intermolecular hydroamination of terminal alkynes [453]. Complex formation reactions of U(VI) with neutral N-donors in DMSO were reported [454]. 

Solvent-Free Three-Component Coupling of Aldehyde, Alkyne and Amine 213... 

In a closely related reaction, Li et al.101 devised a silver-catalyzed three-component coupling between aldehydes, alkynes, and amines. This transformation was really efficient in water and in an ionic liquid, although both required overnight heating at 100°C (Table 10.6). In this reaction, a silver acetylide that was sufficiently nucleophilic to add to the iminium ion that formed by condensation of the amine on the aldehyde was certainly produced.8... 

The coupling of the three components -aldehyde, alkyne and amine- has been called A3 coupling. 7 It delivers propargyl amines, which are important synthetic intermediates and, in contrast to previously used routes, avoids the use of strong-base reagents such as BuLi, ethylmagnesium bromide or LDA, and the need for the kinds of solvents necessary for these reagents. 

Half-sandwich lanthanide alkyl complexes and, subsequently oranolanthanide amides were found to be highly efficient catalysts for the cross-coupling reactions of carbodiimides with alkynes and amines, respectively [136, 137]. Although the half-sandwich lanthanide alkyl complexes can also catalyze the dimerization of alkynes, no homodimerization product is observed in the reaction of alkynes with carbodiimides. These reactions offer a wide scope for the substrates of terminal alkynes and amines, respectively [138]. 

The proposed mechanism for the addition of terminal alkynes and amines to carbodiimides is shown in Figure 8.40. The organolanthanide alkynyl or amide formed in situ is the active intermediate, and the key step is the hydrolysis of a lanthanide amidinate or guanidinate species. 

Figure 8.40 The proposed mechanism for the addition of alkyne and amine to carbodiimide.

Certain ynamides are obtained from 1-alkynes and amine derivatives (e.g., 3-acylindoles, imidazolidinones, oxazolidinones, and sulfonamides) by coupling under oxygen, using the CuCl2-pyridine catalyst. 

Dehydrogenative silylation. I-Alkynes and amines are converted to silyl derivatives by hydrosilanes with iridium carbonyl" and ytterbium-imine complexes as catalyst, respectively. 

Bae, I., Han, H. and Chang, S. (2005) Highly efficient one-pot synthesis of iV-sulfonylamidines by Cu-catalysed three-component coupling of sulfonyl azide, alkyne, and amine. Journal of the American Chemical Society, 127, 2038-2039. 

Li Z, Jiang Z, Su W. Fast, solvent-free, highly enantioselective three-component coupling of aldehydes, alkynes, and amines catalysed by the copper(II)pybox complex under high-vibration ball-milling. Green Chem 2015 17 2330-4. 

Use of iron(iii) oxide has been reported for a number of other organic transformations, most notably a 3-component aldehyde, alkyne and amine coupling, and for the C(sp )-H borylation of arenes using bis(pinacolato)diboron. ... 

A -Coupling and Related Reactions Three-component coupling of aldehydes, alkynes, and amines (A -coupling) is a powerful methodology for the synthesis of propargylamines [88], which has been widely explored using Cu-, Ag-, or Au-based catalysts (see Section 3.4.2). 

S. Chang, J. Org. Chem. 2008, 73, 5520-5528. Mechanistic studies on the Cu-catalyzed three-component reactions of sulfonyl azides, 1-alkynes and amines, alcohols, or water dichotomy via a common pathway. 

M. Kidwai, V. Bansal, A. Kumar, S. Mozumdar, Green Chem. 2007, 9, 742-745. The first Au-nanoparticles catalyzed green synthesis of propargylamines via a three-component coupling reaction of aldehyde, alkyne and amine. 

D. Aguilar, M. Contel, E. P. Urriolabeitia, Chem.-Eur. J. 2010, 16, 9287-9296. Mechanistic insights into the one-pot synthesis of propargylamines from terminal alkynes and amines in chlorinated solvents catalyzed by gold compounds and nanoparticles. 

W.-W. Chen, R. V. Nguyen, C.-J. Li, Tetrahedron Lett. 2009, 50, 2895-2898. Iron-catalyzed three-component coupling of aldehyde, alkyne, and amine under neat conditions in air. 

P. Li, Y Zhang, L. Wang, Chem.-Eur. J. 2009, 15, 2045-2049. Iron-catalyzed ligand-free three-component coupling reactions of aldehydes, terminal alkynes and amines. 

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