Because the SN1 reaction goes through a flat carbocation, we might expect an optically active starting material to give a completely racemized product. In most cases, however, SN1 reactions actually give more of the inversion product. In general, as the stability of the carbocation increases, the excess inversion product decreases. Extremely stable carbocations give completely racemic products. Explain these observations.

Because the SN1 reaction goes through a flat carbocation, we might expect an optically active starting material to give a completely racemized product. In most cases, however, SN1 reactions actually give more of the inversion product. In general, as the stability of the carbocation increases, the excess inversion product decreases. Extremely stable carbocations give completely racemic products. Explain these observations.

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

Chapter9: Addition Via Cyclic Intermediate

Section: Chapter Questions

Problem 5CTQ

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Given that a primary carbocation is less stable than a tertiary carbocation, would you expect that a reaction that creates a primary carbocation would be more or less responsive to solvent polarity than a reaction that creates a tertiary carbocation, and why?
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For this Sn1 reaction, why are there inversion? And are there any other stereochemistry consequences occurring? If you could please explain in detail, I would really appreciate it. Thank you!
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Under second-order conditions (strong base/nucleophile), SN2 and E2 reactions may occur simultaneously and compete with each other. Show what products might be expected from the reaction of 2-bromo-3-methyl butane (a moderately hindered 2∘ alkyl halide) with sodium ethoxide. Do not worry about stereochemistry in the SN2 product for this problem. Don't forget about stereochemistry.
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Draw the molecule: Under second-order conditions (strong base/nucleophile), SN2 and E2 reactions may occur simultaneously and compete with each other.Show what products might be expected from the reaction of 2-bromo-3-methylbutane (a moderately hindered 2∘∘ alkyl halide) with sodium ethoxide. Do not worry about sterechemistry inther SN2 product for this problem. Don't forget about stereochemistry.
The Stille reaction is similar to the Suzuki reaction. It replaces the alkenyl-organoboron compound of the Suzuki reaction with an alkenyl-organotin compound. (R is an alkyl group such as methyl or butyl.) Unlike the alkenyl-organoboron compound that always has a trans configuration, the alkenyl-organotin compound can have a cis configuration. What is the product of the Stille reaction shown here?