Methyl reaction + alkali atoms

A widely-used model in this class is the direct-interaction with product repulsion (DIPR) model [173—175], which assumes that a generalised force produces a known total impulse between B and C. The final translational energy of the products is determined by the initial orientation of BC, the repulsive energy released into BC and the form of the repulsive force as the products separate. This latter can be obtained from experiment or may be assumed to take some simple form such as an exponential decay with distance. Another method is to calculate this distribution from the quasi-diatomic reflection approximation often used for photodissociation [176]. This is called the DIPR—DIP model ( distributed as in photodissociation ) and has given good agreement for the product translational and rotational energy distributions from the reactions of alkali atoms with methyl iodide. 

The reactions of alkali atoms with methyl iodide exhibit rebound dynamics in which reaction takes place only at small impact parameters... 

Calculations of this type have been carried out for the reactions of alkali atoms with methyl iodide 191>, in discussing isotope effects on the abstraction and substitution processes for reactions T + CH4 and T + CD4192), in the classical H+H2 reaction193) for which typical... 

A few results on polyatomic halogen compounds have been reported. The chemical reaction of alkali atoms with methyl iodide... 

Most aliphatic ketones can lose a proton from either of two carbon atoms adjacent to the carbonyl. The question of which of the possible carbanions or salts is the effective reagent in a given base-catalyzed reaction depends on the nature of the electrophilic reagent with which the ion subsequently reacts. Thus alkyl methyl ketones lose a primary proton in their reactions with alkali and iodine, alkali and an aldehyde, or alkali and carbon dioxide, but lose a secondary proton in certain other reactions. 

Then, contrary to our previous hypothesis, the reaction proceeds via a Bai2 displacement of aniline on DMC. The product, mono-A -methyl aniline (PhNHMe), plausibly adsorbs into the zeohte in a different way with respect to anihne, because different H-bonds (N H — O-zeolite) take place with the solid. As recently reported by Su et al., A-methyl amines also may interact with NaY by H-bonding between the protons of the methyl group and the oxygen atoms of the zeolite this probably forces the molecule a bit far from the catalytic surface in a fashion less apt to meet DMC and react with it. This behavior can account for the mono-A-methyl selectivity observed, which is specific to the use of DMC in the presence of alkali metal exchanged faujasites in fact, the bis-A-methylation of primary aromatic amines occurs easily with conventional methylating agents (i.e., dimethyl sulfate). ... 

The isomeric 3-alkylpurines, in contrast to the parent compounds, are highly reactive at the 2- and 6-carbon atoms. The susceptibility of the 2-carbon to nucleophilic attack is shown by the facility with which 6-oxo-3-methyl-2-methylmercaptopurine (28) is converted by ammonia into the 2-amino (29) and then with alkali into the 2-oxo (30) derivative.75 This reaction sequence explains why the action of aqueous ammonia on the 2-methylmercaptopurine (28) resulted in the isolation of 3-methylxanthine (30) rather than the required... 

A more detailed study of the reaction showed that direct iodination takes place when the hydriodic acid formed in the reaction is neutralized by the addition of alkali,280 hypoiodous acid,559-570 or sodium acetate.671, 572 In order to introduce a second iodine atom, Derbyshire and Waters573 used excess iodine in the presence of silver nitrate and nitric acid and obtained 1,4,5-triiodopyrazole. The iodine atom in the 1-position was readily removed by the action of sulfur dioxide or hydriodic acid. Further treatment of 4,5-diiodopyrazole gave 1,3,4,5-tetraiodopyrazole and hence 3,4,5-triiodopyrazole. Methylation of the nitrogen atom facilitates iodination of the ring.571... 

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