Hydroboration

What is the ideal molar ratio of borane, BH3, to the alkene in a hydroboration?

1 mol borane: 3 mol alkene

Fill in the words to complete each step in liquid spill cleanup.

1. Surround the area with absorbent material, then cover the spill. 2. Scoop up the material and place in a plastic bag. 3. Place the bagged waste in a solid waste container. 4. Wipe down the area with detergent and water.

Determine the order of addition for the reagents in the hydroboration oxidation of an alkene.

1st: Alkene 2nd: Borane solution 3rd: Oxidant and base solution

What is generally the best approach when liquid from a large reagent bottle is needed in an experiment?

Pour some of the reagent from the bottle into a beaker, then use as needed in the procedure.

Hydrogen peroxide use

Hydrogen peroxide is classified as an oxidizer and concentrated solutions can be corrosive. When hydrogen peroxide decomposes, oxygen gas is produced, so rapid decomposition due to a catalyst or heating could be explosive. However, dilute solution are stable for about a year if not contaminated.

Hydroboration of alkene

The hydroboration of an alkene occurs in one concerted step which places the boron of the borane on the less substituted carbon of the double bond. The oxidizing agent then acts as a nucleophile, attacking the electrophilic boron and resulting in the placement of a hydroxyl group on the attached carbon. Thus, the major product of the hydroboration oxidation reaction does not follow Markovnikov's rule.

What is the purpose of a drying agent in the work up of an organic reaction?

To absorb small amounts of water in an organic solution

A student removes a chemical sample from a reagent bottle to be used in an experiment. What should he do with any excess chemical remaining from this sample after the experiment is complete?

Check and see if anyone else can use the chemical. If not, discard in the proper waste container.

In general, which characteristics are necessary for a location to be suitable for chemical storage?

Cool, dry, dark

Identify the best practices to follow when adding the boron reagent to the alkene in a hydroboration oxidation reaction.

Use a thoroughly dry syringe and glassware. Add the boron reagent slowly.

What is the last step of any spill cleanup procedure?

Wipe down the affected area with detergent and water.