Amines from oximes

Asymmetric catalytic reduction reactions represent one of the most efficient and convenient methods to prepare a wide range of enantiomerically pure compounds (i.e. a-amino acids can be prepared from a-enamides, alcohols from ketones and amines from oximes or imines). The chirality transfer can be accomplished by different types of chiral catalysts metallic catalysts are very efficient for the hydrogenation of olefins, some ketones and oximes, while nonmetallic catalysts provide a complementary method for ketone and oxime hydrogenation. 

The synthesis of amines from oximes is exemplified by the reduction of oxime 332 to 333 (99W032453) and of bicyclic oximes (derived from ketones 3 and 23a), for instance, of oxime 387 (Scheme 87) to amine 388 that is acylated to yield potential pharmaceutical agent 390 (92BML1147). Nucleophilic substitution of chloropyridine 384 generates morpholino derivative 385 (76IJB400). 

PREPARATION OF a -ALKYLATED AMINES FROM OXIME SULFONATES WITH TRIALKYLALUMINUM - DIISOBUTYLALUMINUM HYDRIDE... 

It is known that electrochemical reduction of oximes in protic media occurs in two steps the N—O bond is first reduced to form an imine and the latter is then reduced to afford a primary amine1,29. Tallec has shown that the amine from oxime 33 can be trapped intramolecularly (equation 16)35. Interestingly, the SS diastereomer predominates the chiral pyrrolidine ring derivative serves to control the stereochemistry of formation of the new benzylic chiral center. Electrochemical reductive cross-coupling of O-methyl oximes with carbonyl compounds in isopropanol at a tin cathode affords adducts (equation 17) which can be reduced further to 2-amino alcohols36. In this fashion, menthone could... 

Amines from oxime acetates Selective reduction... 

Platinum oxide hydrogen chloride Amines from oximes... 

Sodium tetrahydridoborate I zirconium tetrachloride Amines from oximes or alkoximes s. 44, 33... 

Amines from oxime acetates C = NOAc CHNH2... 

Sodium tetrahydridoboratejnickel chloride Amines from oximes s. 24, 23>s44... 

Further examples of the synthesis of primary amines from oximes, azides, nitriles,isocyanides,aldehydes, and Grignard reagents have also been reported. 

Prim, and sec. amines from oximes Reductive rearrangement s. 72, 411 Cyclic imines from alicyclic nitro compounds... 

Hydrogen sulfide-sodium alcohol Amines from oximes s. 11, 29... 

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