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Chloro-substituted triethylsilylenol ethers derived from cyclohexanoneand related ketones are converted with aluminum powder in the presenceof indium trichloride to functionalized allylic aluminum reagentswhich represent a new type of synthetic equivalent of metal enolates.These allylic organometallics undergo highly diastereoselectiveadditions to aldehydes and methyl aryl ketones, giving aldol productswith a β-quaternary center. [ABSTRACT FROM AUTHOR]

Multicomponent reactions hold the potential to maximize the synthetic efficiency in the preparation of diverse and complex molecular scaffolds. An unprecedented formal [3+1+1+1] annulation approach for the one-step synthesis of fluoroalkylated 2- H -pyrimidines commencing from perfluoroalkyl alkenes, paraformaldehyde, and ammonium carbonate is described. By harnessing readily accessible (CH 2 O) n and cheap (NH 4 ) 2 CO 3 as a formamidine surrogate, this method effectively replaces traditionally preformed amidines with a pyrimidine assembly. The multicomponent reaction proceeds in a step-economical, operationally simple, metal-free, and additive-free manner, featuring a broad substrate scope, excellent functional group compatibility, and scalability. The potential for the synthetic elaboration of the obtained 2- H -pyrimidine is further demonstrated in the alkylation and vinylation of its C2 position.

An unprecedented defluorocyclization of perfluorobutyl tetralones with Na 2 S·9H 2 O was developed for the synthesis of trifluoromethyl 1,2-dithioles, which provided chemists novel access to biologically and pharmaceutically relevant organofluorides. Successive C(sp 3 )-F bond functionalization at the perfluoroalkyl chain is vital for the formation of four C-H/C-S/S-S bonds and a five-membered S-heterocycle assembly. Cheap, weakly toxic, and odorless inorganic sulfide Na 2 S·9H 2 O acts as both a disulfurating precursor and a hydrodefluorinating reagent in this tandem multi-bond-interconverting reaction.

A modular multicomponent reaction of readily available fluoroalkyl alkenes, amidines, ammonium carbonate, and water was developed for the facile construction of β-fluoroalkylated aminovinyl ketones, which provided chemists a novel access to value-added organofluorine compounds. The reaction proceeded regio-/stereoselectively under mild conditions and exhibited good functional group tolerance. Cheap, stable, and low-toxic inorganic salt (NH 4 ) 2 CO 3 was first found to act as both a nitrogen source and a carbonyl equivalent in the multi-bond-forming process.

An efficient palladium-catalyzed cross-coupling of indium homoenolate with aryl halide is described. The reactions proceeded efficiently in DMA at 100 °C to afford the desired products of β-aryl ketones in moderate to good yields. Various important functional groups including COR, COOR, CHO, CN, OH, and NO(2) can be well tolerated in the protocol.

A zinc/indium chloride-mediated pinacol cross-coupling reaction between aldehyde and alpha,beta-unsaturated ketone in aqueous media was developed. The 1,2-diols were obtained in moderate to good yields with up to 93:7 diastereoselectivity.

An efficient method for the Barbier-type alkylation reaction of various nitrones (including chiral version) and alkyl halides in water is described. The amines and hydroxylamines can be obtained in good yields, depending on the judicious choice of the metal complexes used.

An efficient system of In/CuI/InCl3 was developed for Barbier-Grignard-type alkylation reactions of simple imines, using a one-pot condensation of various aldehydes, amines (including aliphatic and chiral version), and alkyl iodides in water or aqueous media. The reactions proceeded efficiently at room temperature to give the desired products in moderate to good yields. Good diastereoselectivities were obtained when using L-valine methyl ester as substrate.