Cu (II)-β-CD as Water-Loving Catalyst for One-Pot Synthesis of Triazoles and Biofuels Intermediate at Room Temperature without Any Other Additive

Abstract

Use water as solvent for the organic synthesis a great choice because it is economical, reduces waste and avoids potentially hazardous reagents versus the conventional solvents. This account presents the Cu(II)‐β‐CD as water soluble green catalyst for the one‐pot conversion benzyl halide to benzyl azide and 1,2,3‐trizoles at room temperature and very short reaction time (15‐70 min). Products are separated without any workup, simple by filtration, with >99 % selectivity and purity. As‐synthesized material was characterized by, HR‐TEM, XPS, FESEM, FT‐IR, TGA and XRD to understand its structural properties as well as attachment of copper by host‐guest interaction. This catalyst can also show effectiveness for the condensed ketone and aldehydes moiety, which produce biofuels intermediate. The recyclability of this catalytic system was tested up to five cycles and only a very slight loss of catalytic activity was detected.

One‐Pot Synthesis of Cyclodextrin‐Doped Cu‐SiO2 Catalysts for Efficient Hydrogenation of Dimethyl Oxalate to Ethylene Glycol

“…Gupta et al. have employed Cu II ‐β‐CD as a water‐soluble green catalyst for the one‐pot conversion of benzyl halide to benzyl azide and 1,2,3‐trizoles at ambient temperature . Kaifer et al.…”

Magnetic Isinglass a Nano‐Bio Support for Copper Immobilization: Cu–IG@Fe3O4 a Heterogeneous Catalyst for Triazoles Synthesis

“…Finally, sodium azide act as both an azidonation reagent and a reducing agent producing in situ click‐ catalytic active Cu I species without additional reducing agent (Scheme ) . A considerable number of protocols have been reported in the litrature on the Huisgen click reaction without using any additional reducing agents –,…”

Synthetic Application of Cyclodextrins in Combination with Metal Ions, Complexes, and Metal Particles

“…Gupta and coworkers prepared a CuSO 4 :βCD complex (CuSO 4 , βCD, NaOH solution). [169] Of varied instrumental characterizations, XPS indicated the presence of Cu 2 + species (Cu 2p 3/2 and Cu 2p 1/2 peaks, respectively, at 931.54 eV and 951.4 eV). Triazole formation in the reaction of benzyl bromides and chlorides with phenylacetylenes and NaN 3 gave excellent product yields under MW heating conditions (89-100 %; 0.4 mol %, H 2 O, 36°C, 1 h).…”

“…Sample CuSO :βCD made by the Gupta group and tested in triazole formation (see Section 7.2) was used in aldol condensation as well. [169] The main objective was to produce biofuel intermediates in the reaction of aromatic aldehydes and methyl ketones. Selected data are collected in Table 35.…”