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[2] [3] This reaction is accepted as a click chemistry reaction given the reactions' high yield, stereoselectivity, high rate, and thermodynamic driving force. Basic schematic of thiol-ene addition reaction. The reaction results in an anti-Markovnikov addition of a thiol compound to an alkene. Given the stereoselectivity, high rate and yields ...
Others, however, insist that such a usage is an abuse of terminology, and limit the Michael addition to the formation of carbon–carbon bonds through the addition of carbon nucleophiles. The terms oxa-Michael reaction and aza-Michael reaction [2] have been used to refer to the 1,4-addition of oxygen and nitrogen nucleophiles, respectively. The ...
The classic [13] [14] click reaction is the copper-catalyzed reaction of an azide with an alkyne to form a 5-membered heteroatom ring: a Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The first triazole synthesis, from diethyl acetylenedicarboxylate and phenyl azide, was reported by Arthur Michael in 1893. [ 15 ]
In organic chemistry, the thiol-yne reaction (also known as alkyne hydrothiolation) is an organic reaction between a thiol (−SH) and an alkyne (−C≡CH). The reaction product is an alkenyl sulfide (−CH=CH−S−). [1] [2] The reaction was first reported in 1949 with thioacetic acid as reagent [3] [4] and rediscovered in 2009. [5]
Reaction with thiols occur in the pH range 6.5–7.5, NEM may react with amines or undergo hydrolysis at a more alkaline pH. NEM has been widely used to probe the functional role of thiol groups in enzymology. NEM is an irreversible inhibitor of all cysteine peptidases, with alkylation occurring at the active site thiol group (see schematic ...
Arthur Michael is remembered today primarily for the Michael reaction, also called the Michael addition. As originally defined by Michael, the reaction involves the combination of an enolate ion of a ketone or aldehyde to an α,β-unsaturated carbonyl compound at the β carbon. [6] Michael was also well known in his day for incorporating ...
Such reactions are conducted in the presence of acidic catalysts. The other principal route to thiols involves the addition of hydrogen sulfide to alkenes. Such reactions are usually conducted in the presence of an acid catalyst or UV light. Halide displacement, using the suitable organic halide and sodium hydrogen sulfide has also been used. [23]
Thiyl radicals are intermediates in the thiol-ene reaction, which is the basis of some polymeric coatings and adhesives. They are generated by hydrogen-atom abstraction from thiols using initiators such as AIBN: [2] RN=NR → 2 R • + N 2 R • + R′SH → R′S • + RH. Thiyl radicals are also invoked as intermediates in some biochemical ...