Oxalyl chloride → [(R)-2,2-Dimethyl-3-(1-methylethylidene)cyclobutyl]methyl (S)-2-methylbutanoate

Participants

Reaction Steps

A method for making [(R)-2,2-dimethyl-3-(1-methylethylidene)cyclobutyl]methyl (S)-2-methylbutanoate (2), said method comprising (or consisting essentially of or consisting of) reacting (1R,3S)-3-acetyl-2,2-dimethylcyclobutanecarboxylic acid [(cis)-pinononic acid] with methyl magnesium chloride to form (1R,3S)-3-(1-hydroxy-1-methylethyl)-2,2-dimethylcyclobutanecarboxylic acid (3) or reacting (1R,3S)-3-acetyl-2,2-dimethylcyclobutanecarboxylic acid [(cis)-pinononic acid] with methyl lithium, and then methyl magnesium chloride to form (1R,3S)-3-(1-hydroxy-1-methylethyl)-2,2-dimethylcyclobutanecarboxylic acid (3); reacting (1R,3S)-3-(1-hydroxy-1-methylethyl)-2,2-dimethylcyclobutanecarboxylic acid (3) with phosphorus oxychloride to form (1R,5S)-4,4,6,6-tetramethyl-3-oxabicyclo[3.1.1]heptan-2-one (4); reacting (1R,5S)-4,4,6,6-tetramethyl-3-oxabicyclo[3.1.1]heptan-2-one (4) with p-toluenesulfonic acid to form (R)-2,2-dimethyl-3-(1-methlethylidene)cyclobutanecarboxylic acid (5); reacting (R)-2,2-dimethyl-3-(1-methlethylidene)cyclobutanecarboxylic acid (5) with lithium aluminum hydride to form [(R)-(−)-2,2-dimethyl-3-(1-methylethylidene)cyclobutyl]methanol [(R)-maconelliol] (6), and reacting [(R)-(−)-2,2-dimethyl-3-(1-methylethylidene)cyclobutyl]methanol (6) with oxalyl chloride and (S)-2-methylbutanoic acid to form [(R)-2,2-dimethyl-3-(1-methylethylidene)cyclobutyl]methyl (S)-2-methylbutanoate [(R)-maconelliyl (S)-2-methylbutanoate] (2).

Provenance & Evidence