1- bromo-2-propyl radical

Alkenes and Alkynes I. Ionic and Radical Addition Reactions more stable, the 1-bromo-2-propyl radical, 5, or the 2-bromo-1 -propyl radical, 6 ... 

Examine spin density surfaces for l-bromo-2-propyl radical and 2-bromo-l-propyl radical (resulting from bromine atom addition to propene). Eor which is the unpaired electron more delocalized Compare energies for the two radicals. Is the more delocalized radical also the lower-energy radical Could this result have been anticipated using resonance arguments ... 

Spin density surface for l-bromo-2-propyl radical shows location of the unpaired electron. 

From C-H bond-dissociation energies of alkanes (see Table 4-6), the ease of formation and stabilities of the carbon radicals is seen to follow the sequence tertiary > secondary > primary. By analogy, the secondary l-bromo-2-propyl radical, 5, is expected to be more stable and more easily formed than the primary 2-bromo-1-propyl radical, 6. The product of radical addition should be, and indeed is, 1-bromopropane ... 

Vaughan et al. (103) studied the photobromination of ethylene, propylene, 1-butene, isobutene, and vinyl chloride in the gas phase and found in every case where a distinction could be made that the product was almost entirely the so-called abnormal addition product in terms of the Markownikoff s rule. However, the more recent work of Skell et al. (95) shows that 2-bromo-w-propyl radical may rearrange very rapidly to 1-bromo-isopropyl radical. In view of this the observed exclusive terminal addition of Br atoms in the case of propylene could be in part due to rapid rearrangement. 

Free-radical chlorination of either w-propyl or isopropyl bromide gives 1-bromo-2-chloropropane, and of either isobutyl or / r/-butyl bromide gives l-bromo-2-chloro-2-methylpropane. What appears to be happening Is there any pattern to this behavior ... 

Cyclopropanoxyl radicals were generated by thermal and photochemical decomposition of cyclopropyl nitrites.The nitrites were prepared from cyclopropanols and nitrosyl chloride in pyridine, and they decomposed at low temperatures often below room temperature. A mixture of -bromo and jS-nitroso ketones was formed from the photolysis of pentamethylcyclo-propyl nitrite (19) in bromotrichloromethane. " ... 

Bromo-2-fluoro biphenyl intermediate, foam builders Alkenyl succinic anhydride intermediate, food additives Soy acid Stearyl alcohol intermediate, food emulsifiers Caprylic/capric acid Tallow acid intermediate, food supplements (tablet form) Cetyl alcohol intermediate, food wrap Vinylidene chloride monomer intermediate, fragrances p-t-Butyl toluene t-Butyl-m-xylene Citral Cyclopentanone Diethyl toluene diamine Dimethyl hexynediol 1,2-Methylenedioxybenzene 2-Methylpentanal Myrcene n-Propyl bromide intermediate, fragrances cosmetics Acetic anhydride n-Butyraldehyde n-Butyric acid Butyric anhydride 2-Ethylhexoic acid Isobutyric anhydride 2-Methylpropanal Propionic anhydride intermediate, fragrances personal care Butyric anhydride Isobutyric anhydride intermediate, free-radical polymerization initiators... 

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