Stereoselective construction of cis-2,6-disubstituted tetrahydropyrans via the reductive etherification of delta-trialkylsilyloxy substituted ketones: total synthesis of (-)-centrolobine.
[reaction: see text] The stereoselective intramolecular reductive etherification of delta-trialkylsilyloxy substituted ketones with catalytic bismuth tribromide and triethylsilane provides a convenient method for the construction of cis-2,6-disubstituted tetrahydropyrans. This method was highlighted in the key step of an expeditious total synthesis of the antibiotic, (-)-centrolobine.
Evans
P Andrew
PA
Department of Chemistry, 800 East Kirkwood Avenue, Indiana University, Bloomington, Indiana 47405, USA. paevans@indiana.edu
Cui
Jian
J
Gharpure
Santosh J
SJ
D003500:Cyclization; D007659:Ketones / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011714:Pyrans / Q000138:chemical synthesis*; D013237:Stereoisomerism
D007659:Ketones; D011714:Pyrans; C432457:centrolobin