8. When (1R,2R)-2-bromocyclohexanol is treated with NaOH, the product does not exhibit a broad IR stretch at 3000-3500 cm³¹ and does not rotate plane polarized light. However, when (1R,2S)-2-bromocyclohexanol is treated with NaOH, the product exhibits a strong, broad IR signal at 3000-3500 cm³¹, and is found to be optically active. Draw the two starting materials and propose a mechanism for their reactions with NaOH that is consistent with these observations. (16 pts)

An unknown compound C of molecular formula C6H12O32 exhibits a strong absorption in its IR spectrum at 1718 cm−1 and the given 1H NMR spectrum. What is the structure of 1H NMR spectrum. What is the structure of C?

An unknown compound C of molecular formula C6H12O3 exhibits a strong absorption in its IR spectrum at 1718 cm−1 and the given 1H NMR spectrum. What is the structure of C?

When compound A (C5H12O) is treated with HBr, it forms compound B (C5H11Br). The 1H NMR spectrum of compound A has a 1H singlet, a 3Hdoublet, a 6H doublet, and two 1H multiplets. The 1H NMR spectrum of compound B has a 6H singlet, a 3H triplet, and a 2H quartet. Identifycompounds A and B.

Treatment of W with CH3Li, followed by CH3I, affords compound Y (C7H14O) as the major product. Y shows a strong absorption in its IR spectrum at 1713 cm−1, and its 1H NMR spectrum is given below, (a) Propose a structure for Y. (b) Draw a stepwise mechanism for the conversion of W to Y.

Treatment of W with CH3Li, followed by CH3I, affords compound Y (C7H14O) as the major product. Y shows a strong absorption in its IR spectrum at 1713 cm−1, and its 1H NMR spectrum is given below. (a) Propose a structure for Y. (b) Draw a stepwise mechanism for the conversion of W to Y.

Reaction of p-cresol with two equivalents of 2-methylprop-1-ene affords BHT, a preservative with molecular formula C15H24O. BHT gives the following 1H NMR spectral data: 1.4 (singlet, 18 H), 2.27 (singlet, 3 H), 5.0 (singlet, 1 H), and 7.0 (singlet, 2 H) ppm. What is the structure of BHT? Draw a stepwise mechanism illustrating how it is formed.

11 8. When benzene is treated with Reagent(s) A followed by Reagent(s) B, Compound P (CaHCIO) is the major product. If the order of reagents is reversed, Compound Q (also CaHCIO) is formed instead (see the scheme below). Both P and Q have a strong IR absorption around 1685 cm, H and "C NMR spectra of P and Q are shown below. Draw the structures of P and Q and list the Reagents A and B. Benzene 10 1. A 2. B 9 Compound P ¹H NMR Compound Q ¹H NMR 2:2 السر 2:1:1 ppm 5 ppm : 3 3 Benzene DEPT-90 DEPT-135 0 DEPT-90 200 180 200 DEPT-135 1. B 2. A 180 160 160 140 12 140 120 120 100 ppm Compound P 13C NMR 2 peaks 60 BO Compound Q 13C NMR 100 ppm 80 60 40 -8 20 20

(2R,3S)-2-Bromo-3-phenylbutane undergoes an E2 elimination when treated with sodium methoxide. Draw all possible Newman projections for the bond relevant for the elimination reaction, and use those Newman projections to explain the stereochemical outcome of the reaction. Draw the final product and provide its IUPAC name.

Which set of underlined hydrogens has its 1H NMR signal at a higher frequency?