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Two approaches involving intramolecular and intermolecular cyclization, respectively, have been developed for the direct and practical construction of a series of important benzo[ f ]pyrrolo[1,2- a ][1,4]azepines by using Brønsted acid catalysts. Upon catalysis by TsOH, the intramolecular dehydroxylation/ring closure of 3-hydroxy-2-[2-(1 H -pyrrol-1-yl)benzyl]isoindolin-1-ones provided various racemic benzo[ f ]pyrrolo[1,2- a ][1,4]azepines in high yields. Furthermore, enantioenriched benzo[ f ]pyrrolo[1,2- a ][1,4]azepines were also obtained by chiral phosphoric acid catalyzed intermolecular addition of [2-(1 H -pyrrol-1-yl)phenyl]methanamines to 2-formylbenzoates under mild conditions. [ABSTRACT FROM AUTHOR]

Despite the widespread use of naphthamide atropisomers in biologically active compounds and asymmetric catalysis, few catalytic methods have succeeded in the enantioselective synthesis of these compounds. Herein, a chiral Brønsted acid (CBA) catalysis strategy was developed for readily scalable dynamic kinetic resolution of challenging ortho-formyl naphthamides with pyrrolylanilines. The chiral axis of the atropisomeric amide and a stereogenic center were simultaneously established for a new family of potential biologically active pyrrolopyrazine compounds with high enantio- and diastereoselectivities (up to >20 : 1 d.r. and 98 : 2 e.r.). Epimerization experiments of its derivatives reveal that the N-substitution of the nearby stereogenic center could affect the configurational stability of the axially chiral aromatic amides. These results might be useful for the construction of other kinds of novel axially chiral molecules with a low rotational barrier. [ABSTRACT FROM AUTHOR]

A Chiral Brønsted acid catalyzed asymmetric intramolecular ring‐closing alkylation of inert pyrroles with α, β‐unsaturated ketones has been developed. This approach gave a wide range of 4‐phenyl‐4,5‐dihydro‐6H‐benzo[f]pyrrolo[1,2‐a]azepin‐6‐ones in high yields with good enantioselectivities under mild reaction conditions. [ABSTRACT FROM AUTHOR]

A highly enantioselective regiodivergent addition of alkoxyallenes to pyrazolones was developed to afford multiply functionalized alkylated products bearing a quaternary carbon stereocenter in high yields with excellent stereoselectivities. One approach is enabled by palladium catalysis, thus leading to branched allylic pyrazol-5-ones under mild reaction conditions. The other is catalyzed by a chiral Brønsted acid to give linear products exclusively. Moreover, the usefulness of this new method was highlighted by converting the allylic products into other interesting multifunctionalized pyrazolone derivatives which would be of great potential for the exploitation of pharmaceutically important molecules. [ABSTRACT FROM AUTHOR]

A Brønstedacid accelerated Pd-catalyzed asymmetric allylicalkylation of azlactones with simple allylic alcohols under mild reactionconditions has been realized, which provides a direct and readilyscalable approach for the synthesis of all-carbon quaternary allylicamino acid derivatives in excellent yields and good enantioselectivities. [ABSTRACT FROM AUTHOR]

The back cover of the journal "Angewandte Chemie International Edition" is presented.