Herein we report the formation and interesting reactivity of several azepino[4,5-b]indole heterocycles. Initially, a key intramolecular Heck reaction is used to efficiently create the azepino[4,5-b]indole seven membered ring containing an exocyclic double bond. Treatment of the olefin with ozone results in an unprecedented secondary reaction of the Criegee intermediate, through intramolecular o...

An approach to the synthesis of pseudo-oligosaccharides based on the cross-metathesis reaction between distinct sugar-olefins, followed by intramolecular cyclization of the obtained heterodimer, is presented. In particular, the relative efficiency of two alternative approaches, the straightforward cross-metathesis reaction and the two-step procedure (self-metathesis followed by cross-metathesis...

A family of chiral triazolium salts has been developed for inducing the asymmetric intramolecular Stetter reaction. The use of an aminoindanol-derived catalyst affords optimal results, with the product keto esters formed in 82-97% ee and very good chemical yield. Aromatic and aliphatic aldehydes are equally competent substrates for this reaction. The reaction conditions are reasonably mild and ...

Intramolecular dissipation has recently been invoked by S&lag, Grotemcyer and Levine to interpret dynamical processes in highly excited large molecules. In such problems there is diffusive motion in the presence of a potential. In addition, there are two (or mom) reaction processes which proceed at a finite rate. We present the solution of the Smoluchowski equation for the yields (branching fra...

Intramolecular C±H insertion by Rh-mediated carbenoids has attracted considerable interest in recent years. In addition to its synthetic applications, there have been extensive investigations into the mechanism of this reaction. We have recently studied the electronic e€ects of this reaction through the measurement of the relative reactivities of Rh-mediated carbenoid insertion into a series of...

A formal, metal-free, [2 + 2 + 2] cycloaddition strategy is described based on a cascade of two pericyclic processes. The first step involves an intramolecular propargylic ene reaction of a 1,6-diyne to generate a vinylallene, which then reacts in an inter- or intramolecular Diels-Alder reaction with an alkenyl or alkynyl dienophile. Reactions involving unsymmetrical alkenyl and alkynyl dienoph...

The imine intermediate generated by the addition of primary amine to the cinnamaldehyde is trapped by the N-isocyaniminotriphenylphosphorane (Ph3PNNC) and a carboxylic acid, and leads to the formation of the corresponding iminophosphorane intermediate. The 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediate. The reactions were comp...

A highly diastereo- and chemoselective intramolecular nickel-catalyzed cycloaddition of alkene- and alkyne-tethered alkynylidenecyclopropanes is reported. The method constitutes the first fully intramolecular [3 + 2 + 2] alkylidenecyclopropropane cycloaddition occurring via a proximal cleavage of the cyclopropane and makes it possible to build relevant 6,7,5-tricyclic frameworks in a single-pot...

The role of water in the proton transfer mechanism between the carboxylic and the amino group in tryptophan was studied through the direct, intramolecular reaction in presence of a continuum and the single water molecule mediated, intermolecular reaction in vacuum and in presence of a continuum. The introduction of the continuum reduced the activation barriers for the proton transfer from the n...

A highly enantioselective intramolecular Stetter reaction of aromatic and aliphatic aldehydes tethered to different Michael acceptors has been developed. Two triazolium scaffolds have been identified that catalyze the intramolecular Stetter reaction with good reactivity and enantioselectivity. The substrate scope has been examined and found to be broad; both electron-rich and -poor aromatic ald...