Upon treatment of 3-chloro/bromobenzoic acids with hindered lithium dialkylamides (LDA or LTMP) at-50° C, lithium 3-chloro/bromo-2-lithiobenzoates are generated. These dianions can be trapped as such to afford after electrophilic quenching a variety of simple 2- substituted-3-chloro/bromobenzoic acids. The 3-bromo-2-lithiobenzoate is less stable than the corresponding 3-chloro derivative and partly eliminates lithium bromide, thus setting ...
