Carbon atoms, reaction

Volume 8 Volume 9 Volume 10 Volume 12 Volume 13 Proton Transfer Addition and Elimination Reactions of Aliphatic Compounds Ester Formation and Hydrolysis and Related Reactions Electrophilic Substitution at a Saturated Carbon Atom Reactions of Aromatic Compounds Section 5. POLYMERISATION REACTIONS (3 volumes)... 

The chemical reactivity of the organoruthenium and -osmium porphyrin complexes varies considerably, with some complexes (M(Por)R2, M(Por)R and Os(OEP)(NO)R) at least moderately air stable, while most are light sensitive and Stability is improved by handling them in the dark. Chemical transformations directly involving the methyl group have been observed for Ru(TTP) NO)Me, which inserts SO2 to form Ru(TTP)(N0) 0S(0)Me and Ru(OEP)Me which undergoes H- atom abstraction reactions with the radical trap TEMPO in benzene solution to yield Ru(OEP)(CO)(TEMPO). Isotope labeling studies indicate that the carbonyl carbon atom is derived from the methyl carbon atom. "" Reaction of... 

Electronically excited states of organic molecules, acid-base properties of, 12,131 Energetic tritium and carbon atoms, reactions of, with organic compounds, 2, 201 Enolisation of simple carbonyl compounds and related reactions, 18,1 Entropies of activation and mechanisms of reactions in solution, 1,1 Enzymatic catalysis, physical organic model systems and the problem of, 11, 1 Enzyme action, catalysis of micelles, membranes and other aqueous aggregates as models of, 17. 435... 

Some significant observations can be made from these results. Straight-chain terminal olefins are the most reactive. Little if any difference exists between 2- and 3-internal, linear olefins. Branching is important only if present at one or more of the olefinic carbon atoms reaction becomes more difficult as branching increases. Cyclic olefins react in an irregular fashion, but all are less reactive than terminal, linear olefins. 

Me3SnPPh2 will add to allenes under photochemical conditions, giving two regioiso-meric products32. The predominant species is that in which the phosphine residue attaches to the central carbon atom (reaction 23). The overall yield, and relative proportions of 16 and 17 produced, depends on the nature of the substituent R. For R = H, yield = 78%, ratio 16 17 = 89 11 for R = Me, yield = 67%, ratio = 73 27 for R = Bu, yield = 58%, ratio = 88 12. 

Electronically excited states of organic molecules, acid-base properties of, 12, 131 Energetic tritium and carbon atoms, reactions of, with organic compounds, 2, 201... 

The remaining steps consist in the union of the adsorbed olefin and its derivative, the half-hydrogenated state, with an adsorbed hydrogen atom, reactions which occur with retention of configuration of the substituted carbon atom, reactions (3) and (4),... 

Energies and Spin States in Carbon Atom Reactions. 465... 

Molecular Beam Studies of Carbon Atom Reactions. 493... 

MOLECULAR BEAM STUDIES OE CARBON ATOM REACTIONS... 

For a discussion of the formation of biomolecules in carbon atom reactions see P. B. Shevlin, D. W. McPherson, and P. MeUus, Tbe Reaction of Atomic Carbon with Ammonia. The Mechanism of Formation of Amino Acid Precursors, J. Am. Chem. Soc. 1983, 105, 488 and G. Flanagan, S. N. Ahmed and P. B. Shevlin, The Formation of Carbohydrates in the Reaction of Atomic Carbon with Water, J. Am. Chem. Soc. 1992, 114, 3892. 

For a combined experimental and computational approach to carbon atom chemistry see C. M. Geise, C. M. Hadad, F. Zheng, and P. B. Shevlin, An Experimental and Computational Evaluation of the Energetics of the Isomeric Methoxyphenylcarbenes Generated in Carbon Atom Reactions, J. Amer. Chem. Soc. 2002, 124, 355. 

Selective denitration of methyl 4,6-O-benzylidene- and 4,6-O-alkyl-idene-D-hexopyranoside 2,3-dinitrates to yield 3-nitrates has also been achieved by using sodium nitrite in ethanol as the reagent.233,238, 241.242 interestingly, when the nitrate group is on a primary carbon atom, reaction with this reagent takes place to give the primary alcohol,232,241,243 but the conversion may, on occasion, proceed only with... 

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