Using Curved Arrows for Retrosynthetic Analysis

TCE

The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 15 (2010) pp 331-333

Using Curved Arrows for Retrosynthetic Analysis

John W. Keller

Department of Chemistry and Biochemistry, University of Alaska Fairbanks, Fairbanks, AK 99775-6160, jwkeller@alaska.edu
Received December 10, 2009. Accepted January 14, 2010.

Published: 17 September 2010

Abstract. The purpose of this article is to advocate the wider use of curved arrows by organic chemistry students as a tool for retrosynthetic analysis, particularly for synthesis problems involving Grignard-carbonyl additions, aldol-, Claisen-, and Michael condensations, Diels-Alder, and other C‑C bond-forming reactions. This type of problem is challenging because it requires inductive reasoning that is rarely found elsewhere in the curriculum. However, solving retrosynthetic problems becomes easier when one uses several curved arrows to follow deductively the reverse mechanism. The important first steps of several example retro-reactions are described, and the curved arrow versions of these reactions are given in the Supporting Material. The main benefit of this approach is that, once the appropriate type of synthesis reaction is identified, the correct synthons structures can be generated.

Key Words: Laboratories and Demonstrations; organic chemistry; synthesis; undergraduate; problem solving; nucleophilic substitution; mechanism; retrosynthetic; enolate

(*) Corresponding author. (E-mail: jwkeller@alaska.edu)

Article in PDF format (137 KB) HTML format

Supporting Materials:

Table S1 contains the detailed reverse mechanisms of ten synthesis reactions and brief step-by-step procedures for writing the starting compound structures. Table S2 contains example single and multi-step problems with solutions based on curved arrow retrosynthetic analysis. (22 KB).