Bromides 1 -Bromo-2-chloroethane

Chloroethyl bromide (l bromo-2-chloroethane) [ 107-04-0j M 143.4, b Khi-lOO. Washed with cone H2SO4, water, 10% Na2C03 soln, and again with water, then dried with CaCl2 and fractionally distd before use. 

The work with l-bromo-2-chloroethane allowed the influence of the nature of the halogen on its reactivity to be observed as either vinyl bromide or vinyl chloride are formed. The ratio of the chloride to the bromide in the products changed with the nature of the catalyst, being around 0.1 for sulphates of Ni, Co, Mn, Cu, Zn and for silica—alumina, 0.6 for alumina and 5 for KOH—Si02 [179]. 

For example, the rate of displacement of bromide by thiophenoxide ion in l-bromo-2-chloroethane is slowed down by a factor of 5 compared to substitution in the structurally similar 1-bromopropane (Equations 4.13 and 4.14).33 But the... 

Typical Procedure tor Synthesis of Polymers. 4. A solution of BHB (3.18g, 10.0 mmole) and 25 mL of 2N aq. KOH solution was stirred under nitrogen at room temperature for wmin. A solution of a a -di-bromo-p-x] ene (2.20g, 8.33 mmole), benzyl bromide (0.57g, 3.33 mmole), and O.lg tetra-N-butylammonium bromide in 25 mL 1,2-di-chloroethane was added and the resulting mixture refluxed under nitrogen for 18h with vigorous stirring. The reaction mixture, wNch had gone from deep red to colorless, was then cooled to room temperature and 30 mL hexane was added. The resulting precipitate was then filtered and washed with 100 mL distiiled HoO, and dried under vacuum at 80°C for 18h to yield 4.0g (94%) of 4f as a cream colored solid. 

Pyridinethione and 1-bromo-2-chloroethane in dimethylformamide containing potassium carbonate give 2,3-dihydrothiazolo[3,2-a]pyridinium bromide ... 

Dihydrothiazolo(3,2-a]pyri-dinium bromide, from 2-pyridinethiones and l-bromo-2-chloroethane, 761... 

Ethylene bromide see 1,2-Dibromoethane Ethylene carbonate see 1,3-Dioxolan-2-one Ethylene chloride see 1,2-Dichloroethane Ethylene chlorobromide see l-Bromo-2-chloroethane Ethylenediamine see Ethane-1,2-diamine Ethylene dibromide see 1,2-Dibromoethane... 

Reaction with hydrogen bromide (HBr), which, unlike hydrogen chloride (HCl) can undergo both free radical and ionic addition reactions, produces both 1-bromo-2-chloroethane (BrCH2CH2Cl) and 1-bromo-l-chloroethane (CHsCHBrCl). Under free radical conditions (i.e., in the presence of peroxide catalyst), steric effects dictate that the former is the major product (Equation 7.68). 

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