(i) The following two-step synthesis gives compound K as the major product. OH ****| i. NaBH4 ii. CH₂l2, Zn(Cu) K Assign the configuration of the two chirality centres generated in the second step, i.e. in the cyclopropanation step, using CIP rules. (ii) Explain with the aid of a reaction mechanism why the synthesis is highly diastereoselective. (iii) With reference to compound K, explain what is meant by the term 'diastereotopic groups'. (iv) Draw the structures of the enantiomer, and one epimer of K, and give definitions of these terms.

(i) The following two-step synthesis gives compound K as the major product. OH ****| i. NaBH4 ii. CH₂l2, Zn(Cu) K Assign the configuration of the two chirality centres generated in the second step, i.e. in the cyclopropanation step, using CIP rules. (ii) Explain with the aid of a reaction mechanism why the synthesis is highly diastereoselective. (iii) With reference to compound K, explain what is meant by the term 'diastereotopic groups'. (iv) Draw the structures of the enantiomer, and one epimer of K, and give definitions of these terms.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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