Selective reduction strategies based on abundant-metal catalysts are very important in the production of chemicals. In this paper, a method for the electrochemical semihydrogenation and semideuteration of alkynes to form Z-alkenes was developed, using a simple nickel foam as catalyst and H 3 O + or D 3 O + as sources of hydrogen or deuterium. Good yields and excellent stereoselectivities (Z/E up to 20 : 1) were obtained under very mild reaction conditions. The reaction proceeded with terminal and nonterminal alkynes, and also with alkynes containing easily reducible functional groups, such as carbonyl groups, as well as aryl chlorides, bromides, and even iodides. The nickelfoam electrocatalyst could be recycled up to 14 times without any change in its catalytic properties.

Enantioenriched spirocyclic compounds bearing three contiguous stereocenters and high functionalization were obtained through a formal [3+2] cycloaddition reaction catalyzed by a cooperative system. The spiro compounds were synthesized from 4‐arylideneisoxazol‐5‐ones and isocyanoacetate esters using a bifunctional squaramide/Brønsted base organocatalyst derived from a Cinchona alkaloid and silver oxide as Lewis acid. This method afforded two out of the four possible diastereomers with good yields and high enantiomeric excess for both diastereomers.

The first enantioselective formal [3 + 2] cycloaddition between α-isocyanoesters and trifluoromethylketones to give 5trifluoromethyl-2-oxazolines bearing two contiguous stereogenic centers, one of them being a quaternary stereocenter substituted with a CF 3 group, has been developed. The reaction is based upon a multicatalytic approach that combines a bifunctional Brønsted basesquaramide organocatalyst and Ag + as Lewis acid. The reaction could be achieved with a range of aryl and heteroaryl trifluoromethyl ketones, and the resulting oxazolines were obtained with good to excellent diastereo-and enantioselectivity. Recently, on the basis of a cooperative strategy previously reported by Escolano et al. for the asymmetric cycloaddition of isocyanoacetates with vinyl ketones, 14 our group developed a highly catalytic enantioselective cycloaddition reaction between ketones and α-isocyanoesters using a multicatalytic approach that combined a bifunctional Brønsted base

Chiral cyclic ureas (2-imidazolinones) were prepared by the reaction of nitrones and isocyanoacetate esters using a multicatalytic system that combines a bifunctional Brønsted base-squaramide organocatalyst and Ag + as Lewis acid. The reaction could be achieved with a range of nitrones derived from aryl-and cycloalkylaldehydes with moderate diastereo-and good enantioselectivity. A plausible mechanism involving an initial formal [3+3] cycloaddition of the nitrone and isocyanoacetate ester, followed by rearrangement to an aminoisocyanate and cyclization to the imidazolinone is proposed.

A multicatalytic approach that combines a bifunctional Brønsted base-squaramide organocatalyst and Ag as Lewis acid has been applied in the reaction of unactivated ketones with tert-butyl isocyanoacetate to give chiral oxazolines bearing a quaternary stereocenter. The formal [3+2] cycloaddition provided high yields of the corresponding cis-oxazolines with good diastereoselectivity and excellent enantioselectivity, being applied to aryl-alkyl and alkyl-alkyl ketones.