Conformationally restricted nonchiral pipecolic acid analogues.
Practical syntheses of 2-azabicyclo[3.1.1]heptane-1-carboxylic (2,4-methanopipecolic), 2-azabicyclo[2.2.2]octane-1-carboxylic (2,5-ethanopipecolic), and 9-azabicyclo[3.3.1]nonane-1-carboxylic (2,6-propanopipecolic) acids are reported. The synthetic schemes are short (five, seven, and five steps, respectively) and result in reasonably high yields of the title compounds. The key step in the syntheses is the tandem Strecker reaction and intramolecular nucleophilic cyclization of ketones possessing a leaving group at the delta-position.
Radchenko
Dmytro S
DS
Department of Chemistry, Kyiv National Taras Shevchenko University, Volodymyrska Street 64, Kyiv 01033, Ukraine.
Kopylova
Nataliya
N
Grygorenko
Oleksandr O
OO
Komarov
Igor V
IV
D003500:Cyclization; D007659:Ketones / Q000737:chemistry; D008968:Molecular Conformation; D010875:Pipecolic Acids / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism
D007659:Ketones; D010875:Pipecolic Acids