Construction of Condensed Polycyclic Aromatic Frameworks through Intramolecular Cycloaddition Reactions Involving Arynes Bearing an Internal Alkyne Moiety
efficiently afforded arene-fused oxaacenaphthene derivatives through intramolecular [2+4] cycloaddition. Extending the method to arynes bearing a 1,3-diyne moiety led to continuous generation of naphthalyne intermediates through a hexadehydro Diels–Alder reaction. This aryne-relay chemistry enabled the synthesis of a unique aminoarylated oxaacenaphthene derivative and highly ring-fused anthracene derivatives
Reductive Cleavage of Aryl <i>O-</i>Carbamates to Phenols by the Schwartz Reagent. Expedient Link to the Directed <i>Ortho</i> Metalation Strategy
作者:Justin Morin、Yigang Zhao、Victor Snieckus
DOI:10.1021/ol401547d
日期:2013.8.16
efficient method for the reductive cleavage of aryl O-carbamates to phenols, 1 → 2 using the Schwartz reagent is reported. The method is selective, tolerating a large number of functional groups; may be carried out by direct or by an economical in situ procedure; and, notably, establishes a synthetic connection to the directedorthometalationstrategy (Figure 1) allowing new entries into difficult to
Treatment of benzofurans with bis(pinacolato)diboron and Cs2CO3 under nickel-NHC catalysis resulted in the insertion of a boron atom into the C2-O bond of benzofurans to afford the corresponding oxaborins. The scope of benzofuran substrates is wide, and the reactions proceeded without loss of functional groups such as fluoro, methoxy, and ester that are potentially reactive under nickel catalysis.
Cu-catalyzed transannulation reaction of pyridotriazoles: general access to fused polycyclic indolizines
作者:Yi Shi、Vladimir Gevorgyan
DOI:10.1039/c5cc07598j
日期:——
AN EFFICIENT INTRAMOLECULAR TRANSANNULATION REACTION OF PYRIDOTRIAZOLES WITH INTERNAL ALKYNES EN ROUTE TO VARIOUS FUSED POLYCYCLIC INDOLIZINES HAS BEEN DEVELOPED. FOR THE FIRST TIME IT WAS SHOWN THAT IN ADDITION...
Enantioenriched aryne atropisomers having a biaryl stereogenic axis vicinal to the reactive triple bond are demonstrated to exist. These reaction intermediates are easily produced in situ and can undergo the standard aryne cycloaddition chemistry in an enantiospecific manner. Notably, the aryne atropisomers herein have allowed the practical syntheses of a small nanographene, and some triptycene and