1-bromo-2-fluoroethane

An attempt to prepare 1 -bromo-2-fluoroethane by the partial fluorination of ethylene dibromide by means of antimony trifluoride was not very successful. The compound was best prepared by the action of phosphorus tribromide on F.E.A. The compound was relatively non-toxic and the bromine atom rather unreactive, but considerably more reactive than the chlorine atom in chlorofluoroethane. For example, bromofluoroethane was readily converted by means of potassium thiocyanate into 2-fluoroethyl thiocyanate. As a lethal inhalant the toxicity of the thiocyanate was inferior to that of M.F.A. Toxicity by injection, however, appeared to be higher. 

Exercise 10-7 In the formation of ethenebromonium ion from 1-bromo-2-fluoroethane and SbF5 in S02, is the SbFs playing the role of an acid, a base, an electrophile, or a nucleophile How strong a nucleophile do you judge SbF6e to be Explain. 

Bromo-4-ethynylbenzene l-Bramo-2-fluorobenzene l-Bromo-3-fluorobenzene l-Bromo-4-fluorobenzene 1-Bromo-2-fluoroethane Bromofluoromethane... 

Fluoroethyl xanthate, FCH2CH2S-CS-OEt, was a yellow oil formed by the action of sodium xanthate on bromo-fluoroethane. The compound has a l.d. 50 of 50 mg./kg. for subcutaneous injection into mice, thus showing it to be considerably less toxic than M.F.A. 

Bromine trifluoride or chlorine trifluoride in bromine solution reacts smoothly with bromo-fluoroethanes to give a progressive substitution of bromine by fluorine, e.g. formation of 25.81 The relative case of the replacement of bromine in various groups was shown to be CBr, > CBr,F > CHBr, > CBrF, > CHBrF > CH,Br. 

In Chapter vi the introduction of the 2-fluoroethyl group by the action of l-bromo-2-fluoroethane on triethyl phosphite,3 giving diethyl 2-fluoroethylphosphonate (XI), is considered ... 

Priority is first assigned on file basis of the atomic number of the atoms attached directly to the chiral center. Atoms of higher atomic number are given higher priorities. Thus for 1-bromo-l-fluoroethane, the ordering of priorities is Br > F > C > H on the basis of their respective atomic numbers of 35 > 9 > 6 > 1. 

Under appropriate conditions, (5)- 1-bromo- 1-fluoroethane reacts with sodium methoxide to give pure (5)- 1-fluoro- 1-methoxyethane. 

Fluoroethyl)-5,6-dihydro-4/f-l,3,4-oxadiazines are accessible by ring closure of acylhy-drazides with l-bromo-2-fluoroethane (6.17.7.2.2.1) and fully saturated 1,3,4-oxadiazines arise by condensation of ()8-hydroxyethyl)hydrazines with aldehydes (6.17.7.2.3.1). 

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