Benzyl complexes metal hydroxides

Benzyl complexes metal hydroxides chemistry, 358 a-monooxime, 272 Benzylideneimine Schiff bases metal complexes, 721 Beryllium, alkylalkoxy synthesis, 340 ... 

Whereas metal hydride is eliminated from the o--complex intermediates (cf. 309) in Chichibabin aminations, which results in the subsequent reaction of the metal hydride with ammonia or amines and the evolution of hydrogen, the o--complex intermediates can also be oxidized to the corresponding amino-N-heterocycles. Thus, 5-azacinnoline (320) can be aminated with primary and secondary aliphatic or benzyl amines in the presence of potassium hydroxide/potassium ferricyanide to give the corresponding amino derivatives 321 in up to 65% yield. The... 

The hydrolysis of chelated amino acid esters, H2NCHRCO2R, is known to be accelerated by metal ions, most notably cobalt(III). Dramatic enhancements are also observed with copper(II). Mechanistic studies of the hydrolysis of amino acid esters with copper(II) complexes of glycyl-DL-valine and dien (H2HCH2CH2NHCH2CH2NH2) have been reported/ The hydrolysis of benzyl-penicillin (30) by copper(II) salts to give (31) has been further investigated, and it is proposed that the key step involves intramolecular attack by metal-coordinated hydroxide in an intermediate of type (32). 

At first the unsubstimted metal-free quinoxalinoporphinazine 146 (r1 = r2 = r3 = r4 = e X = HH) was obtained in a 67 % yield by heating dinitiile quinoxaline-2,3-dicarboxylic acid in benzyl alcohol and chlorobenzene at 180 °C with metallic lithium followed by the treatment of the resulting complex with dilute hydrochloric acid (Gal pern and Luk yanets 1969) (Scheme 5.35). A higher yield of 146 (R = R = R = R" = H, X = HH) (95 %) is achieved when carried out in fusion with sodium hydroxide at 220 °C within 15 min (Korzhenevskii et al. 2006). Metal-free benzo[g]quinoxalinoporphinazine 146 (R = R" = H, R, R = Zl, X = HH) obtained from 76d as a result of processing sodium pentoxide and... 

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