Question

Provide the missing organic structures. Include stereochemistry where appropriate. Do not draw inorganic by-products.

Part 1) Draw structure A and include all four bonds at chiral centers.
Part 2) Draw structure B.
Part 3) Draw structure C.

Answer 1

The question involves drawing organic structures with correct stereochemistry but does not provide the structures needed. The task relates to understanding and depicting organic compounds, their functional groups, and reactions. Specific exercises in the reference information focus on organic naming and structure drawing skills.

Step-by-step explanation:

The student's question requires the drawing of organic structures, adhering to the principles of stereochemistry, and without depicting inorganic by-products. For Part 1, the specific structure A is not provided, so it cannot be drawn. For Part 2 and Part 3, without the specific details regarding structures B and C, these also cannot be depicted.

However, looking at the reference exercises provided, for compounds like 5-bromo-3-iodoheptanal or 5-bromo-4-ethyl-2-heptanone, one would draw a seven-carbon chain with the appropriate substituents attached at the indicated carbon atoms, adding a carbonyl group at the end carbon for an aldehyde or to the second carbon for a ketone, respectively.

For exercises involving naming and drawing structures of hydrocarbons or the reaction of organic molecules with halogens, it's essential to understand the functional groups, the structure of hydrocarbons, and basic reaction mechanisms.

Answer 2

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Step-by-step explanation:

Part 1) Structure A is the product that results from a halogenation reaction (aka. bromination reaction). This reaction is a specific type of addition reaction. In this reaction, the double bond is broken when two bromine atoms are added to the affected carbons. There are two chiral centers in the product.

Part 2) Structure B is the product that results from a dehydrohalogenation reaction. In the first part of this reaction, a hydrogen from one chiral center and a bromine from the other are removed and replaced by a pi bond (resulting in an alkene) Since there are two equivalents of NaNH₂, this process repeats itself (resulting in an alkyne).

Part 3) Structure C is the product that results from a catalytic hydrogenation reaction. In this reaction, one hydrogen is added to each affected carbon. Lindlar's Catalyst reduces the alkyne to an alkene.