Compound a (c11h16o) has a band in the ir spectrum at 3450 cm–1 (strong, broad) and does not react with pyridinium chlorochromate (pcc) in ch2cl2. compound a does react with hbr to give compound b (c11h15br). compound b reacts with potassium t-butoxide to give compound c (c11h14). ozonolysis of c followed by treatment with zn and water gives ch3cho and compound d (c9h10o). the proton nmr spectrum of compound d is given below. treatment of compound d with ethyl magnesium bromide yields a. draw the structures of compounds a, b, c, and d. 1h nmr of d: δ 8.1–7.5, multiplet, 5h; 2.85, quartet, 2h; 1.30, triplet, 3h.