A sulfonate-based Cu(Ⅰ) metal-organic framework as a highly efficient and reusable catalyst for the synthesis of propargylamines under solvent-free conditions

A new highly efficient and reusable Cu(Ⅰ)-MOF has been developed for the synthesis of propargylamine compounds via the three-component reaction of secondary amines,alkynes.and aromatic aldehydes under solvent-free conditions.The desired propargylamines were obtained in good to excellent yields with a low catalyst loading.The catalyst may be recovered and reused for up to 5 cycles without major loss of activity.This protocol has the advantages of excellent yields,low catalyst loading,and catalyst recyclability.     

One-pot preparation of pyrrole derivatives via the copper-catalyzed [4+1] annulation of propargylic amines with ethyl glyoxylate and phenylglyoxal in the presence of piperidine

We describe how copper(II) chloride efficiently catalyzes the [4+1] annulation of propargylamines with either ethyl glyoxylate or phenylglyoxal functioning as a C1 unit, in the presence of piperidine, which leads to a straightforward and one-pot preparation of pyrrole derivatives. The key feature in this annulation is the in-situ generation of an N,O-hemiacetal intermediate from either the glyoxylate or the glyoxal and a secondary amine.     

The silver salt of 12-tungstophosphoric acid: an efficient catalyst for the three-component coupling of an aldehyde, an amine and an alkyne

A three-component coupling of an aldehyde, an alkyne and an amine to prepare propargylamines was performed using the silver salt of 12-tungstophosphoric acid (Ag₃PW₁₂O₄₀) as a heterogeneous catalyst under mild reaction conditions in the absence of any co-catalyst. A variety of aldehydes and amines were converted to the corresponding propargylamines demonstrating the versatility of the reaction. The Ag₃PW₁₂O₄₀ (AgTPA) catalyst was recovered quantitatively by a simple filtration and reused several times.     

Asymmetric synthesis of trifluoromethylated propargylamines via 1,2-additions of trifluoromethylacetylide to N-tert-butanesulfinyl imines

An efficient method for the asymmetric synthesis of the trifluoromethylated propargylamines was described. Addition of lithium trifluoromethylacetylide, in situ prepared from lithium diisopropylamide and the 2-bromo-3,3,3-trifluoropropene, to various N-tert-butanesulfinyl imines provided a range of trifluoromethylated propargyl sulfinamides. Besides high yields and excellent diastereoselectivities, the additions featured that the diastereoselectivities could be reversed when polar or nonpolar solvent was used. Acidic cleavage of the tert-butanesulfinyl groups delivered highly optically pure trifluoromethylated propargylamines.     

Ultrasound-assisted rapid and efficient synthesis of propargylamines

Ultrasound was used for the addition of metal acetylides to in situ generated imines to generate propargylamines in good to excellent yields using copper iodide in water at ambient temperature. This process is an efficient alternative to traditional heated reactions. A variety of aldehydes and amines were used for this reaction.     

A highly efficient three-component coupling of aldehyde, terminal alkyne, and amine via C-H activation catalyzed by reusable immobilized copper in organic-inorganic hybrid materials under solvent-free reaction conditions

Recycling copper(I) immobilized on organic-inorganic hybrid material behaves as a very efficient heterogeneous catalyst in the three-component Mannich coupling reaction of aldehydes, terminal alkynes, and amines via C-H activation to afford the corresponding products in good to excellent yields under solvent-free reaction conditions.     

ClickEnam. 1. Synthesis of novel 1,4-disubsituted-[1,2,3]-triazole-derived β-aminovinyl trifluoromethylated ketones and their copper(II) complexes

The copper(I) catalyzed cycloaddition reaction of N-Boc propargyl amine (dipolarophile) 1 with benzyl azide (1,3-dipole) 2 was found to proceed smoothly in t-BuOH/H₂O at room temperature, to furnish the corresponding 1,4-disubstituted-[1,2,3]-triazole-derived N-Boc amine 3 in good yield. Deprotection of 3 with trifluoroacetic acid and addition of the trifluoroacetate salt 4 in the presence of triethylamine, with a series of methoxyvinyl(trifluoromethyl)ketones 10-14, gave the corresponding β-aminovinyl trifluoromethylated ketones 15-19 in moderate to good yields. Two copper(II) complexes, one monomer and one dimer with chlorine double bridge, 20 and 21, respectively, were also prepared and their crystal structure determined. β-Aminovinyl trifluoromethylated ketones 15-17 and complexes 20 and 21 have been screened as potential antifungal agents and the antimalarial activity of 15 and 16 were tested against two Plasmodium falciparum strains (3D7 and W2).