T↓ + 100% The first step in this reaction is the transfer of a hydride ion to the carbon of the carbonyl. The hydride acts as a nucleophile and attacks the carbon of the carbonyl. The hydride can either come in via an axial attack or an equatorial attack depending on steric factors and the placement of other substituents on the ring. Below is the reaction scheme. Take note that some arrows are missing so be sure to include those when writing the mechanism in your prelab report. Typically, the axial attack is preferred over the equatorial attack, leading to the alcohol in the equatorial position. This type of reaction is stereoselective since one stereoisomer is preferred over another. For the reaction in this week's experiment, a mixture of diasteriomeric alcohols will be produced and analyzed. 1 of 4 (H₂C) C Figure 1 axial attack equatorial attack (H₂C)₂C- (H₂C) C. Ho HⓇ (H₂C) C- (H₂C) C- # 90% trans 10% cis OH OH If a more sterically hindered reducing agent is used, then the opposite product ratio is observed. If they were to make an axial attack, these hydride reagents would sterically clash with 1,3-diaxial hydrogen

T↓ + 100% The first step in this reaction is the transfer of a hydride ion to the carbon of the carbonyl. The hydride acts as a nucleophile and attacks the carbon of the carbonyl. The hydride can either come in via an axial attack or an equatorial attack depending on steric factors and the placement of other substituents on the ring. Below is the reaction scheme. Take note that some arrows are missing so be sure to include those when writing the mechanism in your prelab report. Typically, the axial attack is preferred over the equatorial attack, leading to the alcohol in the equatorial position. This type of reaction is stereoselective since one stereoisomer is preferred over another. For the reaction in this week's experiment, a mixture of diasteriomeric alcohols will be produced and analyzed. 1 of 4 (H₂C) C Figure 1 axial attack equatorial attack (H₂C)₂C- (H₂C) C. Ho HⓇ (H₂C) C- (H₂C) C- # 90% trans 10% cis OH OH If a more sterically hindered reducing agent is used, then the opposite product ratio is observed. If they were to make an axial attack, these hydride reagents would sterically clash with 1,3-diaxial hydrogen

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

Chapter14: Elimination

Section: Chapter Questions

Problem 23E

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