(Solved): SYNTHESIS OF 1-BROMO-3-CHLORO-5-IODOBENZENE. PART E. PREPARATION OF 4-BROMO-2-CHLORO-6-IODOANILINE ...

SYNTHESIS OF 1-BROMO-3-CHLORO-5-IODOBENZENE. PART E. PREPARATION OF
4-BROMO-2-CHLORO-6-IODOANILINE

What is the limiting reactant in this reaction/Show your work.

Preparation Refer to the online resources to answer Pre-Lab Exercises, access videos, and read the MSDSs for the chemicals used or produced in this procedure. Review Sections 2.9, 2.10, 2.11, and $$2.17$$. Apparatus A 250-mL round-bottom flask, thermometer, ice-water bath, apparatus for magnetic stirring, vacuum filtration, and flameless heating. Setting Up With magnetic stirring, dissolve $$2.5\mathrm{g}$$ of recrystallized 4-bromo-2chloroaniline in $$40\mathrm{mL}$$ of glacial acetic acid in the round-bottom flask and add 10 $$\mathrm{mL}$$ of water to the mixture. In an Erlenmeyer flask, prepare a solution of $$2.5\mathrm{g}$$ of technical iodine monochloride in $$10\mathrm{mL}$$ of glacial acetic acid. Iodination, Work-Up, and Isolation Over a period of 8-10 min, add the iodine monochloride solution to the stirred solution of the aniline. Heat the resulting mixture to $$90^{?}\mathrm{C}$$ with continued stirring and then allow the solution to cool to about $$50^{?}\mathrm{C}$$. Add just enough saturated aqueous sodium bisulfite to turn the color of the mixture bright yellow; record the volume of sodium bisulfite solution required. Dilute the reaction mixture with enough extra water such that the combined volume of the aqueous sodium bisulfite plus the volume of added water is about $$15\mathrm{mL}$$. Cool the reaction mixture in an ice-water bath and isolate the crude product that results by vacuum filtration. Wash the crystals with a small amount of ice-cold $$33\%$$ aqueous acetic acid and then at least $$50\mathrm{mL}$$ of ice-cold water. Press the filter cake as dry as possible. Purification Recrystallize the crude product from acetic acid-water as follows. Mix the product with glacial acetic acid in the ratio of about $$20\mathrm{mL}$$ of glacial acetic acid per gram of product. Heat the mixture and slowly add $$5\mathrm{mL}$$ of water per gram of product to the mixture as it is heating. Terminate heating once dissolution has occurred and allow the solution to cool slowly to room temperature. Complete the crystallization by cooling the mixture in an ice-water bath and isolate the product by vacuum filtration. Wash the product with cold water and air-dry it.