What are the chemicals involved in the following reaction?

Part
1
Preparation of Examples
Example 1
Step 1
A mixture of 4-bromoacetophenone (148 g), dimethyl succinic ester (130 g) and toluene (2.5 L) was mechanically stirred in a suitable reaction flask. Potassium t-butoxide (100 g) was added in one portion and a precipitate formed. After mixing one hour, water (1 L) was added. The recovered aqueous layer was washed with toluene (200 ml) twice and acidified by 12 N HCl to pH of 2. The product was extracted with ethyl acetate and then recrystallized from a mixture of ethyl ether/hexanes (1/1). White crystals (170 g) were obtained. NMR indicated that the product had a structure consistent with (E)-4-(4-bromophenyl)-3-(methoxycarbonyl)pent-3-enoic acid. There should be exactly 7 paragraphs separated by the markdown divider: ***.
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