Ketones transition metal catalysis

Transition metal catalysis in Baeyer-Villiger oxidation of cyclic ketones with formation of lactones 98AG(E)1198. 

Several examples of transition metal catalysis for the synthesis of piperidines appeared this year. Palladium catalyzed intramolecular urethane cyclization onto an unactivated allylic alcohol was described as the key step in the stereoselective synthesis of the azasugar 1-deoxymannojirimycin . A new synthetic entry into the 2-azabicyclo[3.3.1]nonane framework was accomplished through a palladium mediated intramolecular coupling of amine tethered vinyl halides and ketone enolates in moderate yields . A palladium catalyzed decarboxylative carbonylation of 5-vinyl... 

L. V. Dinh, J. Gladysz, Transition Metal Catalysis in Fluorous Media Extension of a New Immobilization Principle to Biphasic and Monophasic Rhodium-Catalyzed Hydrosilylations of Ketones and Enones , Tetrahedron Lett. 1999, 40,8995. 

As shown in Figure 1.26, a chiral Sm(III) complex catalyzes asymmetric reduction of aromatic ketones in 2-propanol with high enantioselectivity. Unlike other late-transition-metal catalysis, the hydrogen at C2 of 2-propanol directly migrates onto the carbonyl carbon of substrate via a six-membered transition state 26A, as seen in the Meerwein-Ponndorf-Verley reduction. ... 

Ojima and co-workers first reported the RhCl(PPh2)3-catalyzed hydrosilylation of carbonyl-containing compounds to silyl ethers in 1972.164 Since that time, a number of transition metal complexes have been investigated for activity in the system, and transition metal catalysis is now a well-established route for the reduction of ketones and aldehydes.9 Some of the advances in this area include the development of manganese,165 molybdenum,166 and ruthenium167 complex catalysts, and work by the Buchwald and Cutler groups toward extension of the system to hydrosilylations of ester substrates.168... 

Enantioselective isomerization of olefins for preparation of optically active olefins has great synthetic potential with a long tradition [1] and the non-stereoselective version is probably the most intensively investigated reaction in transition metal catalysis [2]. In particular, stereoselective hydrogen migration in a-functionalized olefins, for example allyl alcohols and allylamines [3], affording optically active aldehydes, ketones and amines, is part of the standard repertoire of enantioselec-... 

Benzoyl formate decarboxylase from Pseudomonas putida has been used to synthesize chiral 2-hydroxy ketones and bis(a-hydroxy) ketones, which find their use as pharmaceutical intermediates and as new multidentate ligands for asymmetric transition metal catalysis, respectively.272 273 Combining this decarboxylase activity with AdH has allowed all the stereoisomers of 1 -phenyl-propane- 1,2-diol to be synthesized.274... 

G. Strukul, Transition Metal Catalysis in the Baeyer-Villiger Oxidation of Ketones , Angew. Chem. Int. Ed. Engl. 1998, 37, 1198-1209. 

G. Strukul, Transition Metal Catalysis in the Baeyer-Villiger Oxidation of Ketones, Angew. 

The nitroaldol (Henry) reaction, first described in 1859, is a carbon-carbon bondforming reaction between an aldehyde or ketone and a nitroalkane, leading to a nitroalcohol adduct [29]. The nitroalcohol compounds, synthetically versatile functionalized structural motifs, can be transformed to many important functional groups, such as 1,2-amino alcohols and a-hydroxy carboxylic acids, common in chemical and biological structures [18, 20, 30, 31]. Because of their important structural transformations, new synthetic routes using transition metal catalysis and enzyme-catalyzed reactions have been developed to prepare enantiomerically pure nitroaldol adducts [32-34]. 

Chiral alcohols, respectively hydroxy groups, are a common motive in natural products and bioactive compounds. Therefore, the asymmetric reduction of ketones is a frequently used procedure. In contrast to the asymmetric reduction of imines vide infra), only few organocatalytic methods to reduce ketones are known, and mostly transition metal catalysis or enzymatic methods are used. The... 

Strukul G. Transition metal catalysis in the Baeyer-Villiger oxidation of ketones. Angcw. Chem. Int. Ed 1998 37 1198-1209. 

The transition metal catalysis of this tandem (cascade) reaction involving [3,3]-sigmatropic rearrangement (since it would be the carbonyl oxygen of the acetate forming a new bond to the p-acetylenic atom) followed by the formal Myers-Saito cyclization of allene 3.524 results in the formation of aromatic ketones 3.525 in up to 94% yield (Scheme 3.29) [265]. 

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