Annulation of ketones with vinamidinium hexafluorophosphate salts: an efficient preparation of trisubstituted pyridines.
alpha-Aryl ketones react with vinamidinium hexafluorophosphate salts to give access to the corresponding 3-arylpyridines. The annulation reactions proceed in good to excellent yields with vinamidinium salts containing electron-withdrawing groups at the beta-position (R(2)). The reaction was applied to the preparation of the COX-2 specific inhibitor 5-chloro-3-(4-methylsulfonyl)phenyl-2-(2-methyl-5-pyridinyl)pyridine (1), as well as a series of analogues.
Marcoux
J F
JF
Department of Process Research, Merck & Co., Inc., P.O. Box 2000, Rahway, New Jersey 07065, USA. jeff_marcoux@merck.com
Corley
E G
EG
Rossen
K
K
Pye
P
P
Wu
J
J
Robbins
M A
MA
Davies
I W
IW
Larsen
R D
RD
Reider
P J
PJ
D016861:Cyclooxygenase Inhibitors / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism; D005459:Fluorides / Q000737:chemistry* / Q000378:metabolism; D007659:Ketones / Q000737:chemistry* / Q000378:metabolism; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry / Q000378:metabolism
C413804:5-chloro-3-(4-methylsulfonyl)phenyl-2-(2-methyl-5-pyridinyl)pyridine; D016861:Cyclooxygenase Inhibitors; D007659:Ketones; D011725:Pyridines; D005459:Fluorides