Trityl Isocyanide as a Mechanistic Probe in Multicomponent Chemistry: Walking the Line between Ugi- and Strecker-type Reactions
作者:Răzvan C. Cioc、Hans D. Preschel、Gydo van der Heijden、Eelco Ruijter、Romano V. A. Orru
DOI:10.1002/chem.201600285
日期:2016.6.1
multicomponent chemistry. This reagent can be employed as a cyanide source in the Strecker reaction and as convertible isocyanide in the preparation of N‐acyl amino acids by Ugi 4CR/detritylation and free imidazo[1,2‐a]pyridin‐3‐amines by a Groebke–Blackburn–Bienaymé 3CR condensation/deprotection protocol. The mechanisms of these three classical MCRs intersect at the common N‐trityl nitrilium ion intermediate
The directamination of cyanohydrins with amines via a catalytic cyano-borrowing reaction was developed. The transformation features broad substrate scope, excellent functional group compatibility, and very mild and simple operations. Moreover, a titanium catalyst supported by quinine and (S)-BINOL ligands enabled an asymmetric cyano-borrowing reaction with moderate to high enantioselectivity.
Nucleophilic Phosphine-Catalyzed Intramolecular Michael Reactions of <i>N</i>-Allylic Substituted α-Amino Nitriles: Construction of Functionalized Pyrrolidine Rings via 5-<i>endo</i>-trig Cyclizations
作者:Da En、Gong-Feng Zou、Yuan Guo、Wei-Wei Liao
DOI:10.1021/jo500418s
日期:2014.5.16
Pyrrolidine rings are common moieties for pharmaceutical candidates and natural compounds, and the construction of these skeletons has received much attention. α-Amino nitriles are versatile intermediates in synthetic chemistry and have been widely used in the generation of multiple polyfunctional structures. Herein, a novel nucleophilic phosphine-catalyzed intramolecularMichaelreaction of N-allylic
Controllable Regioselective Construction of Both Functional α-Methylene-β- and -γ-amino Acid Derivatives Through an Organocatalyzed Tandem Allylic Alkylation and Amination
A new controllable and regioselectiveallylicalkylation and amination reaction has been developed for the highly selective construction of compounds containing α-alkylidene-β-amino acid and α-methylene-γ-butyrolactam moieties. Furthermore, on the basis of this controllable strategy, multicomponent tandem reactions have also been accomplished. The subsequent transformations of the densely functionalized
Synthesis of 1,2-Disubstituted Indoles from α-Aminonitriles and 2-Halobenzyl Halides
作者:Anne-Katrin Bachon、Till Opatz
DOI:10.1021/acs.joc.5b02659
日期:2016.3.4
The α-alkylation of deprotonated Strecker products derived from primary amines and aromatic aldehydes with 2-halobenzyl halides furnishes intermediates that can be cyclized to 1,2-disubstituted indoles in moderate to high yields (up to 94% over two steps) by microwave-assisted copper- or palladium-catalyzed intramolecular cross-coupling.