Protonated amino-olefin

Complexes with this formulation satisfy the generally accepted criteria for structural features required in an antitumor-active platinum complex, but are expected to possess kinetic advantages when compared to the prototype antitumor platinum complex, cis-dichloro-diamineplatinum (II). Complexes have been prepared where L is a monoprotonated diamine and also where L is a protonated amino-olefin. All complexes have been examined for cytotoxicity against L1210 leukemia in cell culture, and selected compounds have been tested for antitumor activity vivo (LI210 leukemia in BDF mice). One compound, where L is protonated 3-amino-quinuclidine, has significant vivo activity, with T/C approaching 150%. 

In the absence of protonation, the neutral amino-olefin is, in principle, capable of coordination as a chelate ligand, utilz-ing both the olefin ir-system and the nitrogen lone pair. This would produce a neutral complex of type V, which should also be activated toward the substitution reaction of equation (1), and. 

Protonated Amino Radicals. The reac.tion of hydroxyl amine with TiCl, in aqueous, acidic methanol results in the formation of the simplest protonated amino radical, NH,T. This radical added readily to butadiene and to simple olefins to form products which were the result of coupling of the intermediate B-aminoalkyl radicals ( ). The addition reactions of protonated di-alkylamino radicals were described in a series of elegant papers by Neale and his co-workers (5-10). The radicals were generated from the appropriate N-chloroamines in presence of the unsaturated system. The most effective acid solvent combination was found to be 4M sulfuric acid in glacial acetic acid, but other acid/solvent combinations were also used. The reactions proceeded by chain mechanisms, which were initiated by light or by... 

The reaction was most effective when X was an electron withdrawing substituent, but only because this suppressed the competing ionic chlorination of the double bond. In some cases, the ionic chlorination was the predominant reaction. Protonated amino radical addition to unsubstituted olefins, acetylenes and al-lenes, however, gave acceptable yields of products, particularily in the case of the sterically unhindered substrates. The products obtained from the acetylenes were the a-chloroketones or aldehydes. 

Nitramines are known to photodissociate from their jt,jt state to give aminyl and nitric oxide radicals in the presence of an acid the aminyl radicals are protonated to give aminium radicals, which can initiate addition to olefins. As a synthetic reaction, photolysis of nitramines in the presence of acids can be conveniently run under oxygen to give oxidative addition similar to those shown in equation 145 indeed TV-nitrodimethylamine is photolysed with triene 299 under such conditions to give a mixture of 301 and 302, similar to results observed in the oxidative nitrosamine photoaddition169. To simplify the isolation, the crude products are reduced with LAH to form the open-chain amino alcohol 303. Some other oxidative photoadditions of N-nitro dimethylamine to other olefins are reported. As the photoreaction has to use a Corex filter and product yields are no better than those shown by nitrosamines, further investigations were scarcely carried out. 

New catalyst design further highlights the utility of the scaffold and functional moieties of the Cinchona alkaloids. his-Cinchona alkaloid derivative 43 was developed by Corey [49] for enantioselective dihydroxylation of olefins with OsO. The catalyst was later employed in the Strecker hydrocyanation of iV-allyl aldimines. The mechanistic logic behind the catalyst for the Strecker reaction presents a chiral ammonium salt of the catalyst 43 (in the presence of a conjugate acid) that would stabilize the aldimine already activated via hydrogen-bonding to the protonated quinuclidine moiety. Nucleophilic attack by cyanide ion to the imine would give an a-amino nitrile product (Scheme 10). 

The 13C-, 15N- and -NMR spectral data for a series of simple l-amino-2-nitroalkenes are collected in Table 30. The greater electron-withdrawing character of the nitro group as compared with carbonyl results in downfield shifts of the resonances of C(2) ( + 10 to +14 ppm), the enaminic nitrogen ( + 23.2 to + 27.4 ppm) and the olefinic protons [ + 0.8 to +1.0 ppm for H(l) +1.5 to = 1.8 ppm for H(2)] of 2-nitroenamines with respect to enaminones. This deshielding does not affect C(l), which has in fact a lower chemical shift ( — 5.5 to — 10.2 ppm) in 2-nitroenamines. The NMR spectra show that 2-nitroenamines with a primary or a secondary amino groups exist in solution as solvent-dependent equilibrium mixtures of E- and Z-isomers. The... 

This alkaloid (LXXI) was isolated from the leaves of Funtumia elastica (63). The NMR-spectrum disclosed the presence of two primary amino groups, one olefinic proton (multiplet at 4.7 t), one secondary, and two tertiary methyl groups. On Ruschig deamination the alkaloid afforded progesterone and on methylation with formic acid-formaldehyde it yielded a tetramethyl derivative which proved to be identical with the known (64) 3j8,20a-bisdimethylaminopregn-5-ene. 

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