2-bromopropanoate

Another example of oxygen as a neighbouring group occurs in the hydrolysis of the 2-bromopropanoate anion (39) at low [eOH], which is also found to proceed with retention of configuration (40). The rate is found to be independent of [eOH], and the reaction is believed to proceed ... 

Nucleophilic substitution, aliphatic, 31, 45, 77-100 Ag catalysis, 97 allyl halides, 85 ambident nucleophiles, 97 benzyl halides, 84, 91 bridgehead halides, 86 bromomethane, 78 2-bromopropanoate, 94 1-bromotriptycene, 87 carbanions in, 100,288... 

The phenomenon of halotropism occurs in the reaction of tribromoacetic, 2-bromopropanoic and fnm -3,4-dibromocyclopentane-l-carboxylic acid with sulfur tetrafluoride. Tribromoacetic acid reacts at 25 C to give l,l,2-tribromo-l,2,2-trifluoroethane (6a) in 95% yield, while the other two acids give mixtures of trifluoromethyl derivatives 7 and rearranged 1,1,2-tri-fluoroalkanes6.110 The halogen shifts confirm the carbocationic mechanism of the fluorination reaction (vide supra). 

Bromopropanoic acid Ammonia Alanine (65-70%) Ammonium bromide... 

Exercise 18-20 Optically active sodium 2-bromopropanoate is converted to sodium 2-hydroxypropanoate in water solution. The product has the same stereochemical configuration at C2 as the starting material and the reaction rate is independent of added OH9 at moderate concentrations. At higher concentrations of OH°, the rate becomes proportional to the OH3 concentration and the 2-hydroxypropanoate formed has the opposite configuration to the starting material. Write appropriate mechanisms to explain these facts. Give your reasoning. (It may be helpful to review Sections 8-5 and 15-11.)... 

The synthesis of ethyl 2-bromopropanoate (Expt 5.150) illustrates the preparation of an acyl chloride and its ready bromination in the a-position in the presence of red phosphorus. The resulting bromoacyl chloride is converted into the a-bromoester on reaction with an alcohol. 

Place 2 litres (1760g, 36 mol) of concentrated ammonia solution (d 0.88, 35% w/w) (1) in a large (e.g. Winchester) bottle, cool thoroughly in an ice bath and pour in slowly 77 g (0.5 mol) of 2-bromopropanoic acid (Expt 5.164). Close the bottle with a rubber bung held in place with wire, and leave at room temperature for 4 days. Concentrate the solution to about 250 ml by distillation under reduced pressure using a rotary evaporator apply the vacuum with caution in the initial stages when most of the excess of ammonia is being removed. Filter, concentrate further to 150 ml, cool in ice and add 750 ml of... 

A one-pot alkoxymercuration-bromodemercuration of acrylate esters provides a versatile access to 3-alkoxy-2-bromopropanoic acids (equation 148)969. 

Enantiomerically pure (S)-2-bromopropanoic acid reacts with concentrated sodium hydroxide to give (R)-lactic acid. The reaction goes with inversion and is a typical S 2 reaction—and a good one too, since the reaction centre is adjacent to a carbonyl group (see Chapter 17). 

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