An investigation is reported of the stereochemistry of the Claisen rearrangement of 2-(5-phenyl-2-adamantylidene) ethyl vinyl ether (1-Ph) and of allyl (5-fluoro-2-adamantylidene) methyl ether (2-F). Both ethers undergo the rearrangement principally with the newly forming bond at the zu face (i.e., syn to the 5-substituent), showing that this bond in the transition state is electron deficient from the standpoint of both termini. The two derivatives of the latter ether in which the one remaining hydrogen has been replaced by a phenyl group or an oxide anion function (3-F and 4-F) were also examined. In these two instances as well, the zu face of the vinyl terminus is favored; in all four cases, the ratio of stereoisomers is in the range of 1.33 to 1.56. The introduction of a negative charge at this terminus evidently fails to bring about the onset of the type of delocalization envisioned in the Anh model. Taken together with the oxy-Cope and allyl vinyl sulfoxide rearrangements studied earlier, these [3,3] sigmatropic shifts all exhibit a remarkably uniform face selectivity.
Modified aza-claisen rearrangement: Generation and isomerization of allyl enammonium salts
作者:John C Gilbert、K.P.A Senaratne
DOI:10.1016/s0040-4039(01)80240-9
日期:1984.1
Base-promoted reaction of ketones and diethyl (diazomethyl)phosphonate in the presence of allylic amines affords allylic enamines in good yields. These enamines undergo [3,3]-sigmatropic rearrangement upon alkylation and heating at 80°C to iminium salts which can be hydrolysed to aldehydes. The procedure allows generation of quaternary carbon centers under mild reaction conditions.
Chemistry of sulfines. 12. Unusually facile thio-Claisen rearrangement of 1-alkenyl 2-alkenyl sulfoxides: a new sulfine synthesis
作者:Eric Block、Saleem Ahmad
DOI:10.1021/ja00309a063
日期:1985.11
L'oxydation des allyl vinyl sulfures en leurs sulfoxydes correspondants conduit a une acceleration remarquable de la vitesse de processus sigmatrope [3+3], conduisant a des sulfines isolables pouvant etre converties en les composes carbonyles dans des conditions douces
L'oxydation des allylvinylvinylsulfes en leurs sulfoxydes 通讯员管道 a une 加速 remarquable de la vitesse de processus sigmatrope [3+3], conduisant a des sulfines isolables pouvant etre converties en les composes carbonyles dans des conditions douces
Introduction of two carbon appendages at a carbonyl carbon. Application to double chain branching and spiro annulation operations
作者:Elias J. Corey、Joel I. Shulman
DOI:10.1021/ja00721a042
日期:1970.9
Mukherjee Ashis, Wu Gianhong, le Noble William J., J. Org. Chem, 59 (1994) N 12, S 3270-3274
作者:Mukherjee Ashis, Wu Gianhong, le Noble William J.
DOI:——
日期:——
GILBERT, J. C.;SENARATNE, K. P. A., TETRAHEDRON LETT., 1984, 25, N 22, 2303-2306