Keto amines

Q. CO. C(COaEt). N(CO. Ph). CH. CHj. CHPr. CH, was hydrolysed and decarboxylated and the unstable keto-amine hydrogenated in methyl alcohol with palladised charcoal as catalyst to the... 

Sulphonic acids Indigo-disulphonio acid (indigocarmine), 304. Amines, 308. Keto-amines P3rramidone, 452. Allan-toin, 474. Murexide, 499. Amino-carboxylic acids Histidine, 513. Hydrazines, 531. Azo compoimds, 535. 1... 

Lactams Lactams represent a special type of C=N system due to the tautomerization between the lactam (keto amine) and lactim (hydroxyimine) forms. The lactim form is much more favored for cyclic than for non-cyclic amides of carbocyclic acids. In the reaction of complex 2b with N-methyl-e-caprolactam, a simple ligand exchange reaction occurs and complex 87 can be isolated. With P-propiolactam, the alkenyl-amido complex 88 is formed, which indicates an agostic interaction. The reaction of complex 1 with e-caprolactam gives, after elimination of the alkyne and of molecular hydrogen, complex 89 with a deproto-nated lactam in a r]2-amidate bonding fashion [47]. 

In a recent study, reaction of chiral allenamides 54 with m-chloroperbenzoic acid (m-CPBA) led to an epoxidation and subsequent ring opening by w-chlorobenzoic acid [19] The resulting a-keto aminals 55 were obtained with high diastereoselectiv-ity (Scheme 17.19). 

Organic dye nanoparticles of DHIA and DHBIA (the chemical structures are shown in Fig. 1) have been synthesized in THF/water mixed solvent by a reprecipitation method [32]. These dye molecules possess a 2-(2-hydroxyphenyl) benzothiazole (HBT) unit, which is known to be more stable as an enol imine form in the ground state and as a keto amine form in the excited state [32, 33] (Fig. 6). The nanoparticles exhibited the AIEE phenomenon mainly due to a restricted intramolecular motion, that is, impediment to free rotation of two end-substituted HBT units around single bonds. It is interesting to note that the... 

A subsequent process, still reliant on salt resolution, is described in Scheme 14.8. In this case, (3-keto amine 34 was converted to carbamate 35, which was then transformed into the desired amino alcohol intermediate 36. The resolution was performed in three distinct stages (1) initial resolution of the racemate, (2) racemization of the (/J)-enriched mixture, and (3) second-order asymmetrically induced crystallization of the (5)-salt. 

Enantioselective catalytic hydrogenation has also been apphed to the preparation of optically active duloxetine intermediates (Scheme 14.15). In one such report, (3-keto amine 31 was converted to amino alcohol 32a in excellent enantiomeric excess without... 

Compared with other transition elements,1092 few complexes of Schiff s bases or /5-keto amines with chromium(III) are known. Most work has been done with ligands (228) to (231) and their complexes and the interrelations between the more important of them are set out in Table 94 and Schemes 103 and 104. 

Many preparative methods have been used, with variable success oxidative decarbonylation of Cr(CO)6 by the ligand,1093,1094 reaction of the appropriate amine with [Cr(sal)3J (salH is salicylaldehyde), reaction of the ligand, either produced in the reaction mixture or preformed,1095 with hydrated or anhydrous CrCl3, hydrated Cr111 acetate,1096 or [CrCU(THF)3],1097-1099 and aerial oxidation of the chromium(II) cpmplex produced in sifu.1099-1101 No well-established chromium(II) complexes, except of a few /3-keto amines (Section 35.3.9.1), have been isolated. 

A convenient asymmetric synthesis of a-hydroxyaldehydes begins with the addition of a Grignard reagent to the methoxycarbonyl aminal (238) prepared from methyl hydroxy-methoxyacetate and diamine (236) (79CL705). Treatment of the derived keto aminal (239) with a second Grignard reagent and hydrolysis of the resulting hydroxy aminal (240) yields the optically active a-hydroxyaldehyde (241). Enantiomeric excesses vary between 78 and... 

The 15N magnetic resonance studies of the pyrimidine bases or their derivatives are scarce. Roberts et al.BB have measured the 1H and 15N magnetic resonance spectra of a number of pyrimidines including uracil and 1-methylcytosine. The most important result of this study was the elucidation of the dominant tautomeric structures of uracil and proto-nated 1-methylcytosine as the diketo, 32, and keto-amine form, 7, respectively (cf. Sections II and IV and the spectrum of 1-methylcytosine hydrochloride labeled only in the amino group62). In the case of uracil,85 the two 15N-bonded protons gave two doublets centered at 10.78 and 10.96 ppm (measured downfield from internal tetramethyl-... 

Figure 4. TOP The amount of keto amine-linked glycosylation of insoluble collagen plotted as a function of subject s age. BOTTOM The amount of insoluble collagen plotted as a function of subject s age. Key O. normal +, juvenile-onset diabetic and , maturity-onset diabetic.

IR-spectra of pseudostrychnine in the solid phase and in solution indicate that it exists almost entirely in the carbinolamine form CXCVI. Two other forms might be expected to exist in equilibrium with CXCVI in solution the immonium form CXCVII, produced by proton-catalyzed loss of the hydroxyl group, is totally excluded on steric grounds the keto-amine form CXVIII, on the other hand, almost certainly exists in equilibrium with CXCVI in solution, but in concentrations which escape detection by physical methods. Its presence is deduced from some of the chemical reactions of pseudostrychnine. The easy formation of O-alkyl ethers (125) by interaction with methanol or ethanol even at room temperature almost certainly involves nucleophilic attack of the alcohol molecule on the carbonyl carbon in CXCVIII or in the O-protonated form CXCIX (R = H) to yield a hemiacetal as a first step likewise, the formation of 16-cyanostrychnine (XXV CN instead of OH) must involve addition of cyanide ion to CXCVIII, and the reaction with... 

Optically active a-kytbvxy aldehydes. A synthesis of chiral a-hydroxy aldehydes involves reaction of 1 with methyl hydroxymethoxyacetate to form the methoxycarbonyl aminal 2. The product is treated with a Grignard reagent in the presence of MgCl2 to form the keto aminal 3. A second Grignard reaction with 3 forms an intermediate (a), which is hydrolyzed to 1 and an a-hydroxy aldehyde (4) ... 

Keto Cyanides by Interaction of Alkali Cyanides and /3-Keto Amines 595... 

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