62102-73-2Relevant articles and documents
A new method for the preparation of silyl enol ethers from carbonyl compounds and (trimenthylsily)diazomethane in a regiospecific and highly stereoselective manner
Aggarwal, Varinder K.,Sheldon, Chris G.,Macdonald, Gregor J.,Martin, William P.
, p. 10300 - 10301 (2002)
The reaction of lithium (trimethylsilyl)diazomethane with aldehydes and ketones has been investigated, and it has been found that quenching at low temperature with MeOH followed by addition of Rh2(OAc)4 gave silyl enol ethers in high yields. Quenching with other electrophiles (e.g., deuterium, MeI) gave terminal and substituted silyl enol ethers with complete control over regio- and stereochemistry. The mechanism of this novel process has been mapped out through a combination of deuterium labeling, ReactIR, and isolation of reaction intermediates. Copyright
Mild and selective hydrozirconation of amides to aldehydes using Cp 2Zr(H)Cl: Scope and mechanistic insight
Spletstoser, Jared T.,White, Jonathan M.,Tunoori, Ashok Rao,Georg, Gunda I.
, p. 3408 - 3419 (2007/10/03)
An investigation of the use of Cp2Zr(H)Cl (Schwartz's reagent) to reduce a variety of amides to the corresponding aldehydes under very mild reaction conditions and in high yields is reported. A range of tertiary amides, including Weinreb's amides, can be converted directly to the corresponding aldehydes with remarkable chemoselectivity. Primary and secondary amides proved to be viable substrates for reduction as well, although the yields were somewhat diminished as compared to the corresponding tertiary amides. Results from NMR experiments suggested the presence of a stable, 18-electron zirconacycle intermediate that presumably affords the aldehyde upon water or silica gel workup. A series of competition experiments revealed a preference of the reagent for substrates in which the lone pair of the nitrogen is electron releasing and thus more delocalized across the amide bond by resonance. This trend accounts for the observed excellent selectivity for tertiary amides versus esters. Experiments regarding the solvent dependence of the reaction suggested a kinetic profile similar to that postulated for the hydrozirconation of alkenes and alkynes. Addition of p-anisidine to the reaction intermediate resulted in the formation of the corresponding imine mimicking the addition of water that forms the aldehyde.
A New Synthesis of Aldehydes and Aldehydes-d from Grignard Reagents
Yamashita, Masakazu,Miyoshi, Kanako,Nakazono, Yutaka,Suemitsu, Rikisaku
, p. 1663 - 1664 (2007/10/02)
Aldehydes were prepared from Grignard reagents in high yields using pentacarbonyliron as the carbonylating agent.This reaction was also found to be applicable to the synthesis of aldehydes-d.
