题目

CHE 008B A01 SS1 2025 Lecture 2 - Alcohols with H2SO4

多重下拉选择题

Select True or False. False E1 eliminations can form alkenes between the carbocation and any carbon in the molecule. True Dehydration is the loss of the elements of H2O from a molecule. True Eliminations of alcohols tend to form the more substituted alkene as the major product. False Cis alkenes are preferred over trans alkenes in E1 eliminations. True The mechanism of a reaction describes the flow of electrons. False Alcohols with H2SO4 always form alkenes. False There is no nucleophile present in ROH + H2SO4 True Alcohols can form ethers at moderate temperatures, and alkenes at higher temperatures in the presence of acid.

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思路分析

The prompt presents eight statements to assess as True or False. I will examine each one individually, explaining why it is correct or incorrect based on organic chemistry concepts and typical reaction patterns. 1) 'False E1 eliminations can form alkenes between the carbocation and any carbon in the molecule.' This statement is labeled False. In an E1 reaction, after the leaving group departs to give a carbocation, a base abstracts a proton to form an alkene. The resulting double bond forms between the carbocation-bearing carbon and an adjacent carbon that can support overall alkene stability. Not every adjacent bond is equally feasible: the beta-hydrogen must be on a carbon adjacent to the carbocation, and steric/electronic factors determine which alkene is formed. If the carbonyl or other substituents block certain beta positions, or if rearrangements occur that move the positive charge before elimination,......Login to view full explanation