Methyl imine

A RhCp complex (S,S)-6 (Cp =pentamethylcyclopentadienyl), which is iso-lobal with Ru(rj6-arene) complex (S,S)-5 (Scheme 13), effected the transfer hydrogenation of a cyclic imine substituted by an isopropyl group with an S/C of 200 in the presence of a 5 2 mixture of formic acid and triethylamine to give the R amine in 99% ee (Scheme 13) [31]. When the reaction was performed with an S/C of 1,000, the optical yield decreased to 93%. The methyl imine was reduced with a 91% optical yield. Reduction of a cyclic sulfonimide resulted in the R sul-tam in 81% ee. 

Imines (98) may be lithiated66 if (a) they have no other acidic protons a to C=N and (b) they are A-methyl imines or they have other activation towards a-lithiation. The N-allyl amidines 99, for example, give interesting chiral organolithiums 100 with BuLi.67... 

Propose a mechanism for the hydrolysis of benzaldehyde methyl imine just shown. 

Hexafluoroacetone imine has been prepared by the reaction of hexafluoroacetone with triphenyl phosphine imine,2 by the pyrolysis of N-phenyl-2,2-diaminohexafluoropropane,23 by the reaction of hexafluorothioacetone with hydrazoic acid,4 and by the reaction of ammonia and phosphorus oxychloride with hexafluoroacetone.4,5 The latter method, which is described here, is the most convenient for it does not require preparation of several intermediates or use of pressure equipment. This method has also been used to prepare the imines of other Huoroketones, including the imines of chloropentafluoroacetone, dichlorotetrafluoroacetone, and perfluorodiethyl ketone.5 Substitution of methylamine for ammonia in this procedure gives the N-methyl imine.5... 

Keten Methoxycarbonyl- -(methyl-thio-methyl-imin) E15/3, 2617 [ROOC-CR(CN)-SR3/A]... 

The metabolism of methylamine is believed to occur in two stages. The amino group is initially dehydrogenated to an intermediate imine (methyl imine), which reacts spontaneously with water, forming the corresponding aldehyde (formaldehyde) and ammonia. The final metabolic products, reported to be formic acid and urea or methylurea, are excreted in the urine. To a lesser extent, methylamine is also metabolized to dimethylamine. Methylamine is a normal constituent of mammalian and human urine. 

Figure 1.1 Calculations ofthe LUMO energy in eV (geometry optimized at B3LYP/6 31C(d)) relative to N methyl imine derived from benzaldehyde.

A related reduction of the C = N function in methyl imine derivatives of 3-arylindan-l-one with sodium borohydride gave almost pure c/.v-3-aryl-l-indanamines19. 

The methyl imine may be determined in presence of methoxyl by heating the hydriodide alone in the flask... 

The method of determination by means of the alkyl iodides does not, as a rule, distinguish between ethyl imine and methyl imine in doubtful cases it is necessary to distil a considerable quantity of the hydriodide of the base, and purify and identify the alkyl iodide which is evolved. A second method consists in distilling the base with potassium hydroxide, evaporating the distillate to dryness with hydrochloric acid, separating the organic hydrochlorides from ammonium chloride by means of absolute alcohol and chloroform, and converting the former into pic rates, chloroplatinates, etc., which may then be identified the method must however, be used with caution, as it may lead to errone ous results. 

Condensation of the diester 22 with the methyl imine of piperonal furnished the trans-fused lactam amide 23 which was homologated to 24. Saponification and Friedel-Crafts acylation then provided the crystalline keto lactam 25 which was converted to oxysanguinarine (see Scheme 21.7). ... 

Oxidation of carbon atoms a to a carbonyl, which proceeds through an enol intermediate, is not included. The C—H bond is cleaved in an acid-base process prior to any radical pathway thus, while the radical is essential to the key bond forming event, it is not essential in the C—H functionalization." Similarly, radical oxidation of methyl imines to resonance-stabilized carbocations, trapped by nucleophiles such as azides, is not covered." ... 

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