2. Strychnine (6) is a notorious poison for both humans and rats. The first synthesis of this molecule was achieved by R. B. Woodward over sixty years ago (JACS 1954, 76, 4749-4751). In the last step of Woodward's synthesis, compound 1 was converted into 6 via intermediates 2-5, as shown. a) Draw all curved arrows that show the entire transformation of 1 into 6, and identify the entire sequence of arrow-pushing patterns. You may draw directly on the structures provided. b) For the step in which 4 is transformed into 5, identify the nucleophilic center and the electrophilic center. This step involves the creation of a new chirality center. Determine its configuration and explain why this reaction is enantiospecific (why the other possible configuration is not observed).

2. Strychnine (6) is a notorious poison for both humans and rats. The first synthesis of this molecule was achieved by R. B. Woodward over sixty years ago (JACS 1954, 76, 4749-4751). In the last step of Woodward's synthesis, compound 1 was converted into 6 via intermediates 2-5, as shown. a) Draw all curved arrows that show the entire transformation of 1 into 6, and identify the entire sequence of arrow-pushing patterns. You may draw directly on the structures provided. b) For the step in which 4 is transformed into 5, identify the nucleophilic center and the electrophilic center. This step involves the creation of a new chirality center. Determine its configuration and explain why this reaction is enantiospecific (why the other possible configuration is not observed).

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

Chapter13: Substitution

Section: Chapter Questions

Problem 4E

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