I -Bromopropane

What products would you expect from the reaction of I bromopropane with cache the following ... 

The energy of the E2 transition state for I-bromopropane is similar to that for 2-bromopropane, because the products are the same (propene). So the E2 rate constants for these two compounds will be similar. However. 1-bromopropane, being primary, will have a faster competing SN2 reaction than will the secondary 2-bromopropane. Overall, it is reasonable to estimate that the actual E2 rate for l-bromopropane will be intermediate between the rates for bromoethane and 2-bromopropane. 

Application of this procedure requires knowledge of the partition functions for each molecular conformer, and the energy differences between the conformers. Calculations have been reported for hydrazine, 1-chloropropane, I-bromopropane, and buta-l,3-diene. For each of these molecules, the calculation was simplified by assuming that the... 

The regioselectivity of the addition of HX to an unsymmetrical alkenes i) The addition of HBr to propene the main product is 2-bromopropane. 

This reaction is achieved by heating the monohaloalkane under reflux with ethanollc potassium (or sodium) hydroxide, i.e. potassium (or sodium) hydroxide dissolved in ethanol. The reaction is referred to as a base-induced elimination reaction and to demonstrate more clearly the role of the base in the reaction, it is worth considering the mechanism involved. This is illustrated for the reaction between 2-bromopropane and ethanolic potassium hydroxide ... 

Prop-2-enyl trifluoromethanesulfonate, 1457 Propionyl hypobromite, 1150 Propionyl nitrite, 1181 Propiophenone, 3145 f Propyl acetate, 1971 f Propyl bromide, see 1-Bromopropane, 1237 f Propyl chloride, see 1-Chloropropane, 1239 Propylcopper(I), 1247... 

To the solution of l-phenyl-l-methoxy-2-bromopropane methylamine was added and as a result of the reaction l-phenyl-l-methoxy-2-methylaminopropane was obtained. After that l-phenyl-l-methoxy-2-methylaminopropane on hydrolysis with hydrobromic acid yielded 1-phenyl-l-hydroxy-2-methylaminopropane, i.e. racemic pseudoephedrine. The racemic base was resolved, by crystallization of their tartrates, into I- and d-pseudoephedrine. The base l-pseudoephedrine forms white rhombic crystals, melting point 118°C. The salt pseudoephedrine sulfate may be prepeared by... 

TABLE n.2 Enthalp ies of reaction (AH o) 3nd energy barriers (EB) for the reaction of bromopropane with OH radicals and Cl atoms (kcal mol... 

C3H7Br 2-bromopropane 75-26-3 6.890E-I-09 48.520 3006 C4H604 succinic acid 110-15-6 8.820E+09 59.500... 

The tertiary halide is in parentheses because it usually does not react by an Sn2 mechanism. The primary factor in this order of reactivity is steric hindrance, i.e., the ease with which the nucleophile can come within bonding distance of the alkyl halide. 2,2-Dimethyl-1-bromopropane... 

A An alcohol can be made from propene in a series of reactions. Alcohols can be made directly by adding water (steam, under pressure plus a hot catalyst of phosphoric acid) to an alkene, but can also be made using a series of reactions by, e.g. propene -I- HBr —> 2-bromopropane (in the absence of air) followed by hydrolysis with a hot dilute solution of sodium hydroxide. (2)... 

In this case, the formation of, and subsequent attack by, the bromine radical on the alkene leads to the most stable carbon radical species, namely the secondary radical. This in turn picks up a hydrogen atom from another hydrogen bromide molecule and forms another bromine radical that might continue the reaction. This route produces the 1-bromopropane isomer, and not 2-bromopropane, i.e. the azztz -Markovnikov orientation. This change in regiochemistry, which is caused by the introduction of some radical initiator, is called the peroxide effect, because peroxides are often used as the radical initiator. 

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