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A method for the electrochemical synthesis of sulfinic esters by aerobic oxidative coupling of thiophenols and alcohols has been developed. Using electrons as the redox reagent and O2 in air as the oxygen source, the reactions proceeded smoothly at room temperature, even for a gram-scale preparation. No use of catalyst, clean redox reagent, green and abundant oxygen source, and mild reaction conditions make this strategy eco-friendly.

A lithium chloride catalyzed aza-Michael reaction of pyrazoles to α,β-unsaturated imides has been developed. A range of aromatic and aliphatic α,β-unsaturated imides are found to be suitable for the established method, providing the corresponding aza-Michael adducts in up to 93% yields. The inexpensive catalyst, good substrate tolerance, and ease of scale-up make this procedure highly practical.

1 H -Indazoles are important heterocycles as they are a substantial part in many drugs. Here, a DBU-catalyzed aza-Michael reaction of indazole with enones is described. A variety of aromatic and aliphatic enones are well tolerated and afford the corresponding N 1 -substituted 1 H -indazoles in high to excellent yields with exclusive N 1 -regioselectivity. The use of a metal-free catalyst, good substrate tolerance, mild reaction conditions, and high atom economy make this procedure a direct and facile method for the preparation of N 1 -substituted 1 H -indazoles.

A facile and efficient 1,4-addition of Me 3 SiCN toenones has been achieved with perfect regioselectivity using Cs 2 CO 3 ascatalyst. Thus, with 0.5 mol% of Cs 2 CO 3 and4 equivalents of H 2 O as the additive excellent yields(81-99%) of β-cyanoketones are obtainedwithin one to five hours. Both aromatic and aliphatic enones arefound suitable substrates for this protocol.