A new transition-metal-free amination of pyridine-2-sulfonyl chloride and related N-heterocycles using magnesium amides of type R2NMgCl·LiCl is reported. Additionally, the directed ortho-magnesiation of pyridine-2-sulfonamides using TMPMgCl·LiCl was investigated. Reaction of the magnesium intermediates with various electrophiles and subsequent amination using magnesium amides led to a range of 2,3-functionalized
substituents at C(6) on irradiation are believed to undergo ring opening stereospecifically affording a mixture of two configurationally isomeric diene-ketenes (and descendents thereof)- Exceptions are generally found for those dienones with one C and one O substituent or even with two C substituents, if one of them carries a polar group at a site able to interact through space with the ring CO group. In these
Preparation of Polyfunctional Heterocycles Using Highly Functionalized Aminated Arylmagnesium Reagents as Versatile Scaffolds
作者:David M. Lindsay、Wolfgang Dohle、Anne Eeg Jensen、Felix Kopp、Paul Knochel
DOI:10.1021/ol025597x
日期:2002.5.1
[reaction: see text] Functionalized Grignard reagents, derived from readily available o-iodoaniline derivatives and obtained via a straightforward iodine-magnesium exchange, can be used to prepare a wide range of polyfunctional indoles, quinolines, and quinazolinones.
Peroxycarbenium-Mediated C−C Bond Formation: Applications to the Synthesis of Hydroperoxides and Peroxides
作者:Patrick H. Dussault、In Quen Lee、Hyung-Jae Lee、Richard J. Lee、Q. Jason Niu、Jeffrey A. Schultz、Umesh R. Zope
DOI:10.1021/jo991714z
日期:2000.12.1
while SnCl(4) and trimethylsilyl triflate promote formation of peroxides. Lewis acid-promoted reactions of silylated hydroperoxyacetals furnish silylated hydroperoxides, which can be deprotected to homologated hydroperoxides. Hydroperoxyketals undergo Lewis acid-mediated allylation to furnish 1,2-dioxolanes via attack of hydroperoxide on the intermediate carbocation. Lewis acid-mediated cyclization