Recyclable Polystyrene-Supported Copper Catalysts for the Aerobic Oxidative Homocoupling of Terminal Alkynes

Abstract

Polystyrene-supported copper(II) N,N,N′,N′-tetraethyldiethylenetriamine [Cu(II)-TEDETA] complexes were prepared by immobilization of TEDETA onto crosslinked polystyrene resin, followed by complexation with copper salts. The polystyrene-immobilized CuSO 4 -TEDETA complex efficiently catalyzed the oxidative homocoupling of terminal alkynes under air to give the corresponding 1,3-diynes in up to 99% yield. The catalyst was easily recovered by simple filtration and reused eight times without significant loss of catalytic activity.

Micelle‐Enabled One‐Pot Guanidine Synthesis in Water Directly from Isothiocyanate using Hypervalent Iodine(III) Reagents under Mild Conditions

“…[1][2][3] Since then many elegant reactions have been reported. [4][5][6][7][8][9][10][11][12] Although on-water reactions offer much benefits, wide-spread adoption has been limited by inability of on-water reaction to be adapted to all traditional chemical transformation reactions due to heterogeneous behaviour.I nr ecent years, new developments in surfactant technology created by Lipshutz [13][14][15][16][17][18] and others [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] have significantly made an improvement for aqueous reactions allowing reaction to occur "in-water" via the formation of micelles,t hereby providingh igh reproducibility and reactivity.…”