Organic Chem - Oxidation and Reductions

[gabe1scott]

Homework Statement

Im having some problems with some oxidation and reduction mechanisms. I am not sure if I am doing them correctly.

Homework Equations

1. O=C=O + CH3^-MG⁺⁺I^-

2. Acetone + NH4+, Na+ H3BCN

The Attempt at a Solution

1. I break one of the bonds from the oxygen and protonate it to give me a carboxylic acid. I am not sure if I dehydrate it to form 2-propanol.

2. I don't really know where to start with this one. I think the NH4 adds a hydrogen to the oxygen, and then the carbon nitrile attacks and forces off the OH to form water, leaving Propane substituted with a CN group.

 

[TeethWhitener]

1. O=C=O + CH3-MG++I-

2. Acetone + NH4+, Na+ H3BCN

1. The first one is a Grignard reaction. I've never thought of it specifically as a redox reaction, but I guess it is. Anyway, the methyl anion is highly nucleophilic and attacks the electrophilic carbon on CO₂ to give acetate. Upon acidic workup, the organic product is acetic acid.

2. The second one requires you to know that sodium cyanoborohydride is a weak reducing agent (weaker than sodium borohydride). The combination of acetone and ammonium will give an iminium ion (the carbonyl C=O is replaced with a C=NH₂⁺). The cyanoborohydride reduces this to an amine. So the final product is isopropylamine (2-aminopropane in IUPAC language).