A/N-dimethylaniline

A very interesting approach to optically active sulphoxides, based on a kinetic resolution in a Pummerer-type reaction with optically active a-phenylbutyric acid chloride 269 in the presence of A,N-dimethylaniline, was reported by luge and Kagan (equation 149). In contrast to the asymmetric reductions discussed above, this procedure afforded the recovered sulphoxides in optical yields up to 70%. Chiral a, -unsaturated sulphoxides 270 were prepared via a kinetic resolution elaborated by Marchese and coworkers. They found that elimination of HX from racemic -halogenosulphoxides 271 in the presence of chiral tertiary amines takes place in an asymmetric way leading to both sulphoxides 270 and 271, which are optically active (optical yields up to 20%) with opposite configurations at sulphur (equation 150). 

Enantioselective Friedel-Crafts Reactions. The copper(II) complex of the (5, 5 )-t-Bu-box ligand has been used as catalyst for the reaction of A. N-dimethylaniline with ethyl glyoxylate and it has been found that a highly regio- and enantioselective Friedel-Crafts reaction takes place. This reaction proceeds with the exclusive formation of the para-substituted isomer in up to 91% yield and 94% ee (eq 24). 

Several studies have used NMR spectroscopy to determine the number and identity of drug metabolites in bile. These include the use of NMR spectroscopy to study doxifluridine catabolites in human bile, and C NMR spectroscopy of perfluorinated fatty acids in rat bile and NMR for monitoring the formation of formaldehyde from demethylation of antipyrine. NMR spectroscopy of rat bile has been used to monitor the excretion of paracetamol metabolites. A combination of H and H- - C 2D NMR methods has allowed identification of 4-cyano-A,N-dimethylaniline, cefoperazone and benzyl chloride in rat bile. ... 

The model described by Eq. (8) has also been applied for the quenching of pyrene incorporated into sodium taurocholate aggregates in the presence of 1.0 M NaCl [118]. The recovered association and dissociation rate constants for A, N-dimethylaniline were respectively 1.4 x 10 s and 3.8 x 10 ... 

Like the RRDE (see Sect. 2.4.2.2), the DCE has also been extensively used to study the kinetics and mechanisms of electrode reactions involving following chemical reactions. A good example is the electrooxidation of 4-amino-A, N-dimethylaniline (ADMA), which proceeds by an EC reaction in basic aqueous solution [71]. 

While A/,N-dimethylaniline is an extremely reactive aromatic substrate and is readily attacked by such a weak electrophiles as aryl diazonium ions and nitrosyl ion, this reactivity is greatly diminished by introduction of an alkyl substituent in the ortho position. Explain. 

The N-monosubstituted oxamic acids were converted to free amines with diphenylcarbodiimide. Treatment of 458 with this reagent in methylene chloride (0°C, 1 hr) produced 7a-methoxyamine 462. After acylation with chloroacetyl chloride (A,N-dimethylaniline, 25 C, 16 hr) amide 463 was isolated in 40% yield. Substance 458 reacts with dicyclohexylcar-bodiimide in a different and unfavorable manner to form imidazolidinone 464 (36%) and amidine 465 (6%). Hydrolysis of the former with p-TSA gave dicyclohexylimidazolidinetrione and 7-oxocephem methyl ester (466). 

Propose syntheses of the following compounds from benzene (a) A/.N-Dimethylaniline (b) p-Chloroaniline... 

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