Cleavage of a chiral auxiliary using RCM on an especially sterically crowded alkene: Syntheses of chiral carbo- and heterocycles

• Published in: Journal of organometallic chemistry Vol. 691; no. 24; pp. 5336 - 5355
• Main Authors: Spino, Claude, Boisvert, Luc, Douville, Jasmin, Roy, Stéphanie, Lauzon, Sophie, Minville, Joannie, Gagnon, David, Beaumier, Francis, Chabot, Christine
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-12-2006
• Subjects: Bulky ruthenium alkylidene; Carbocycles; Heterocycles; p-Menthane-3-carboxaldehyde; Ring-closing metathesis; Carbocycles; Heterocycles; p-Menthane-3-carboxaldehyde; Bulky ruthenium alkylidene; Ring-closing metathesis
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/j.jorganchem.2006.07.028

RCM is used to cleave a chiral auxiliary and generate carbo- and heterocycles directly. The alkene bearing the auxiliary has an uncommon steric demand challenging the limits of the catalysts.
Chiral 1,5-, 1,6-, and 1,7-dienes generated in 3–4 steps from chiral auxiliary
p-menthane-3-carboxaldehyde undergo RCM with notable discrepancies in reactivity depending on the nature and number of substituents flanking the central double bond. The chiral auxiliary is thus cleaved releasing a carbo- or heterocycle in the process. Special features concerning the RCM on these especially crowded systems are discussed.