Thermodynamic control will favor energetically stable products even if they require a higher activation energy and more time to produce. Recall that there are two major factors influencing which products of a reaction are preferentially formed: thermodynamics and kinetics. The correct answer is C2 as it is the carbon represented by the asterisk.Ģ) The passage states that upon dehydration of the cyclized product, a thermodynamic mixture of products is formed. C4 was part of the initial five-carbon ring and remains a part of the fused rings structure.It should attach to the original five-carbon ring and is below and to the right of the carbon with the asterisk.

C3 is the alpha carbon that serves as a nucleophile during the intramolecular cyclization.C3 serves as the nucleophile in the aldol condensation reaction and the carbon with the asterisk is two carbons away (up and to the right) from the nucleophilic alpha carbon. C2 is indeed the carbon with the asterisk.C1 is directly attached to C4 and is the carbon to the right of the asterisk.Let’s follow the numbered carbons and determine which one corresponds to the carbon with the asterisk. It then goes on to say that the ring undergoes a dehydration reaction to form the two products 4a and 4b. It mentions that Compound 3 undergoes an aldol condensation to cyclize, another word for forming a ring. Exam 3 Chemistry/Physics Section Passage 1ġ) The best way to approach this question is to take what the passage says about the corresponding steps and try to visualize them.

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