Sodium triacetoxyborohydride, NaBH(OAc)₃, is a mild reducing agent that reduces aldehydes much more quickly than ketones. It can be used to reduce aldehydes in the presence of ketones, such as in the following reaction:

(a) Draw a complete Lewis structure for sodium triacetoxyborohydride.

Show how you would make each compound, beginning with an alcohol of your choice.

(g)

(h)

Compounds containing deuterium (D = ²H) are useful for kinetic studies and metabolic studies with new pharmaceuticals. One way to introduce deuterium is by using the reagent LiAlD₄, equivalent in reactivity to LiAlH₄. Show how to make these deuterium-labeled compounds, using LiAlD₄ and D₂O as your sources of deuterium, and any non-deuterated starting materials you wish.

(c) CH₃CD₂OD

Both NaBH₄ and NaBD₄ are commercially available, and D₂O is common and inexpensive. Show how you would synthesize the following labeled compounds, starting with butan-2-one.

(a)

Suggest the most appropriate reagent for each synthesis, and explain your choice.

(c)

Draw the products of the following reactions. Indicate whether each reaction is an oxidation or a reduction.

a.

b.

c.

Propose a mechanism for the following reaction:

Predict the product of the following reaction sequences.

(c)

Show how you would synthesize the following compounds from the appropriate carboxylic acids or acid derivatives.