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Wittig reaction between substituted phosphonium salts and (hetero)aromatic and alkyl carbonyl compounds in Deep Eutectic Solvents has been developed under a scalable and friendly protocol. Highly efficient reactions were successfully run with a wide range of bases including organic (DBU, LiTMP, t-BuOK) and inorganic (NaOH, K 2 CO 3 ) ones in ChCl/Gly 1 : 2 (mol/mol) as solvent under mild conditions, at room temperature and under air. The proposed protocol was applied to a wide range of substrates, including (hetero)aromatic aldehydes with substituents as halogens (I, Br, Cl), EDG (alkoxy, methyl), EWG (NO 2 , CF 3 ) or reactive groups as CN, esters, and ketones. Vinylic, alkynyl and cycloalkyl, alicyclic and α,β-unsaturated aldehydes can also be used. Highly electrophilic ketones gave good yields. The diastereoselectivity of the reaction is in complete agreement with the E/Z ratio predictable under traditional conditions. We demonstrated that the protocol is scalable to 2 g (5 mmol) of phosphonium salt, furthermore the proposed workup protocol allows to remove TPPO without need of additional chromatographic purification., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

The synthesis of acetals in acidic natural deep eutectic solvents (NADES), in which the solvent itself participates in the catalytic promotion of the reaction, is reported herein. The reaction is performed under feasible conditions, open air, without the need of external additives, catalysts or water-removing techniques, and it is wide in scope. The products are easily recovered, and the reaction medium is fully recycled and reused without weakening of its catalytic activity after 10 times. Remarkably, the entire process has been realized on gram scale., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

A mild and efficient telescoped procedure for the stereoselective alkenylation of simple, non-activated amides using LiCH 2 SiMe 3 and carbonyl compounds as surrogates of alkenyllithium reagents is reported. Our methodology relies on the formation of stable tetrahedral intermediates, which, upon collapse into highly reactive lithium enolates in a solvent-dependent fashion, allows for the assembly of α,β-unsaturated ketones in a single synthetic operation with high stereoselectivity.