Question

can you please explain each step. thanks

1. Using the HNMR spectrum and molecular formula for the product, determine the structure. Complete the synthesis using an organometallic reagent and an aldehyde or ketone. (Full: correct synthesis and HNMR assignment, partial: correct NMR assignments) Br CyH60 Reagents for Synthesis 2 PPM 4.2 ppm, 1H, s 3.2 ppm, 1H, 1.92 ppm, 2H, m 0.98 ppm, 12H, d

Answer 1

Molecular formula: $C_7H_{16}O$

Degree of Unsaturation=$\frac{2C-H+2}{2}=\frac{14-16+2}{2}=0$

There are only four proton signals so the compound must be symmetric

First analyze NMR:

a: broad singlet of 1H at 4.2 ppm, is an exchangeable proton must belong to OH

b: triplet of 1H at 3.2 ppm, a CH group having two neighboring H and bonded to electronegative atom

c: multiplet of 2H at 1.9 ppm, must belong to two CH group as the compound may be symmetric

d: doublet of 12 H at 0.98 ppm, belongs to 4 CH3 group having a neighboring CH group

So structure of the compound (in the box) and synthetic scheme is given below,

Ragents for synthesis:

- a OH - OMgBr 1 Br - H Mg, dry THE MgBr H30+ - - b 1 1 1 - d

1. Mg, dry THF

2. 2-methylpropanal

3. acidic water