Functionalization of N-Tosyl-2-Pyridinone with Silyl Ketene Acetal Catalyzed by Lewis Acid, and Synthetic Studies of Corynantheidol Export

@article{citeulike:298846, abstract = {The reaction of N-tosyl-2-pyridinone with tert-butyldimethylsilyl ketene acetal, catalyzed by a Lewis acid, has been investigated. While both the C-4 Michael adduct 3 and the bicyclic compound 5 were isolated from aluminum chloride- or trimethylaluminum- catalyzed reactions, the former was afforded as the sole product from diethylaluminum chloride- or trimethylsilyl trifluoromethanesulfonate- catalyzed reactions. During investigation of a synthesis of corynantheidol, a method for construction of the key intermediate 30 was accomplished via, (1), the efficient conversion of the enamine moiety to an alkenyl bromide (20\^{o}22), followed by the Sonogashira coupling reduction (22\^{o}23); (2), selective reduction of the acetylene and intramolecular cyclization (25\^{o}26); (3), the coupling reaction with the indole unit (27\^{o}30).}, author = {Hiroya, Kou and Jouka, Rumi and Katoh, Osamu and Sakuma, Takashi and Anzai, Michiko and Sakamoto, Takao}, citeulike-article-id = {298846}, citeulike-linkout-0 = {http://www.arkat-usa.org/ark/ARKIVOC/KF-851H%20as%20published.pdf}, journal = {Arkivoc}, keywords = {orgo}, pages = {232--246}, posted-at = {2005-08-20 01:27:03}, priority = {2}, title = {Functionalization of N-Tosyl-2-Pyridinone with Silyl Ketene Acetal Catalyzed by Lewis Acid, and Synthetic Studies of Corynantheidol}, url = {http://www.arkat-usa.org/ark/ARKIVOC/KF-851H%20as%20published.pdf}, volume = {8}, year = {2003} }

TY - JOUR ID - citeulike:298846 L3 - citeulike-article-id:298846 N2 - The reaction of N-tosyl-2-pyridinone with tert-butyldimethylsilyl ketene acetal, catalyzed by a Lewis acid, has been investigated. While both the C-4 Michael adduct 3 and the bicyclic compound 5 were isolated from aluminum chloride- or trimethylaluminum- catalyzed reactions, the former was afforded as the sole product from diethylaluminum chloride- or trimethylsilyl trifluoromethanesulfonate- catalyzed reactions. During investigation of a synthesis of corynantheidol, a method for construction of the key intermediate 30 was accomplished via, (1), the efficient conversion of the enamine moiety to an alkenyl bromide (20ô22), followed by the Sonogashira coupling reduction (22ô23); (2), selective reduction of the acetylene and intramolecular cyclization (25ô26); (3), the coupling reaction with the indole unit (27ô30). JF - Arkivoc EP - 246 TI - Functionalization of N-Tosyl-2-Pyridinone with Silyl Ketene Acetal Catalyzed by Lewis Acid, and Synthetic Studies of Corynantheidol VL - 8 SP - 232 KW - orgo AU - Hiroya, Kou AU - Jouka, Rumi AU - Katoh, Osamu AU - Sakuma, Takashi AU - Anzai, Michiko AU - Sakamoto, Takao PY - 2003/// UR - http://www.arkat-usa.org/ark/ARKIVOC/KF-851H%20as%20published.pdf ER -