Chemoselective addition of grignard reagents to alkoxycarbonylalkyl-N-imidazolium-N-methyl amides: synthesis of 4-oxo and homologous esters

A method for the synthesis of 4-oxo and homologous esters is achieved by metalation of alkoxycarbonylalkyl-N-imidazolium-N-methyl amides with 1equiv of LDA followed by highly chemoselective addition of 1 equiv of a Grignard reagent.Ministerio de Educación y Cienci

Synthesis of aldehydes from acyl chlorides via 1-(acylmethylamino)-3-methylimidazolium salts

The reaction of acyl chlorides with 1-amino-3-methylimidazolium salts, followed by N-methylation of the resulting H-aminides, afforded 1-(acylmethylamino)-3-methylimidazolium salts which, upon treatment with DIBALHgave aldehydes in good yields. A nalogously, dialdehydes were obtained from the corresponding bis-salts.The authors are grateful for grant (MAH) from Ministerio de Educación y Ciencia\ud and financial support from Comisión Interministerial de Ciencia y Tecnología (CICYT) through the project\ud PB90-028

Synthesis of carbonyl and dicarbonyl compounds from organometallic reagents and N-imidazolium-N-methyl amides and bis-amides

A new method for the synthesis of selective acylating agents is described from the reaction of carboxylic acids with 3-methyl-1-methylamino-3H-imidazol-1-ium salts in the presence of appropriate coupling reagents. The amides and bis-amides thus prepared reacted selectively with organometallics to afford ketones and diketones and with DIBALH to give aldehydes and dialdehydes in high yields.The authors acknowledge the Comisió Interdepartamental de Recerςa i Innovació Tecnológica (CIRIT, project QFN94-4619) for financial support and the Ministerio de Educaci6n y Ciencia for a studentship (M.A.H.)

1-(Benzoylamino)-3-methylimidazolium chlorochromate (BAMICC), a new selective and mild reagent for the oxidation of allylic and benzylic alcohols

A new mild chromium(VI) oxidizing reagent, the 1-(benzoylamino)-3-methylimidazolium chlorochromate (BAMICC) has been prepared as a stable yellow-orange solid which selectively oxidizes allylic and benzylic alcohols, including those bearing basic nitrogens, to carbonyl compounds.The authors are grateful for a grant (MAH) received from Ministerio de Educación y Ciencia and for financial support from Comisión lnterministerial de Ciencia y Tecnología (CICYT, project PB90-0284

Synthesis and structure of complexes of acyl N-aminides with zinc(II) salts

The structures of complexes obtained by reacting acyl N-aminides and ZnCl2 were ascertained by X-ray analysis and were show to incorporate one Zn atom and two molecules of the N-aminide in a distorted tetrahedral geometry. Bis-aminides act as bidentate ligands forming ZnLCl2 complexes.The authors acknowledge the Comisió lnterdepartamental de Recerςa i lnnovació Tecnologica (CIRIT, project QFN94-4619) for financial support and the Ministerio de Educación y Ciencia for a studentship (MAH.