Phosphoramidite accelerated copper(i)-catalyzed [3 + 2] cycloadditions of azides and alkynes

Abstract

Monodentate phosphoramidite ligands are used to accelerate the copper(i)-catalyzed 1,3-dipolar cycloaddition of azides and alkynes (CuAAC) rapidly yielding a wide variety of functionalized 1,4-disubstituted-1,2,3-triazoles; Cu(i) and Cu(ii) salts both function as the copper source in aqueous solution to provide excellent yields.

Kinetics and Mechanism of Michael-type Reactions of Ethyl Propiolate with Alicyclic Secondary Amines in H2O and MeCN: Solvent Effect on Reactivity and Transition-State Structure

“…[16][17][18][19] Although the βnuc value of 0.51 for the reactions in MeCN may represent a concerted mechanism, 20 we propose the reaction does not proceed through TS1 on the basis of the fact that: (1) The amines are less reactive in MeCN than in H2O. (2) Hammett ρ values were reported to be larger in the aprotic solvent than in H2O.…”

“…[1][2][3][4][5][6][7][8] However, most studies have been focused on the stereochemistry of the reaction products (e.g., Z-or E-isomer) due to synthetic interests. [5][6][7][8] We performed Michael-type reactions of activated acetylene derivatives such as 3-butyn-2-one (1) 9 and 1-(X-substituted phenyl)-2-propyn-1-ones (2) 10 with a series of primary amines to investigate reaction mechanism. The reactions were reported to proceed through a stepwise mechanism with rate-determining nucleophilic attack on the electrophilic carbon atom followed by fast proton transfer.…”

“…[1][2][3][4][5][6][7][8] It is well known that alkynes conjugated with an electron withdrawing group (EWG) such as alkynones and acetylenic esters undergo Michael-type reactions with various nucleophiles. [1][2][3][4][5][6][7][8] However, most studies have been focused on the stereochemistry of the reaction products (e.g., Z-or E-isomer) due to synthetic interests.…”

“…[1][2][3][4][5][6][7][8] It is well known that alkynes conjugated with an electron withdrawing group (EWG) such as alkynones and acetylenic esters undergo Michael-type reactions with various nucleophiles. [1][2][3][4][5][6][7][8] However, most studies have been focused on the stereochemistry of the reaction products (e.g., Z-or E-isomer) due to synthetic interests. [5][6][7][8] We performed Michael-type reactions of activated acetylene derivatives such as 3-butyn-2-one (1) 9 and 1-(X-substituted phenyl)-2-propyn-1-ones (2) 10 with a series of primary amines to investigate reaction mechanism.…”

Well-defined copper(i) complexes for Click azide–alkyne cycloaddition reactions: one Click beyond

“…Phosphoramidite ligands have also been reported to accelerate CuAAC. 51 The active copper(I) species were generated in situ from CuSO 4 ·5H 2 O and sodium ascorbate in the presence of MonoPhos 29, although higher copper loadings (1 mol %) and purification on column chromatography were required with this catalytic system.…”