Azulene-2-boronic acid pinacol ester was conveniently transformed into 2-substituted azulenes bearing carboxyl, formyl, ester, or amino groups, which are difficult to access by conventional methods. Furthermore, the azulene-2-carboxylic acid thus synthesized was subjected to the Ugi four-component condensation to obtain a dipeptide-type product containing an azulene skeleton.
Mechanistic Studies into Amine-Mediated Electrophilic Arene Borylation and Its Application in MIDA Boronate Synthesis
作者:Viktor Bagutski、Alessandro Del Grosso、Josue Ayuso Carrillo、Ian A. Cade、Matthew D. Helm、James R. Lawson、Paul J. Singleton、Sophia A. Solomon、Tommaso Marcelli、Michael J. Ingleson
DOI:10.1021/ja3100963
日期:2013.1.9
computational study, the borylation of activated arenes at 20 °C proceeds through an S(E)Ar mechanism with borenium cations, [Y(2)B(amine)](+), the key electrophiles. For catecholato-borocations, two amine dependent reaction pathways were identified: (i) With [CatB(NEt(3))](+), an additional base is necessary to accomplish rapid borylation by deprotonation of the borylated arenium cation (σ complex), which otherwise
Aromatic amides bearing 2-azulenyl group on the amide nitrogen were synthesized and their structures were investigated. The π-electron density of the N-aryl group was found to influence the cis-trans conformational preferences of these compounds in solution. X-ray crystallography revealed that the plane of the 2-azulenyl ring has a strong tendency to lie coplanar with the amide plane when the azulene group
Ring Expansion-Annulation Strategy for the Synthesis of Substituted Azulenes and Oligoazulenes. 2. Synthesis of Azulenyl Halides, Sulfonates, and Azulenylmetal Compounds and Their Application in Transition-Metal-Mediated Coupling Reactions
作者:Aimee L. Crombie、John L. Kane、Kevin M. Shea、Rick L. Danheiser
DOI:10.1021/jo048698c
日期:2004.12.1
Stille, and Suzuki coupling reactions. Reaction of the azulenyl triflate 84 with pinacolborane provides access to the azulenylboronate 91, which participates in Suzuki coupling reactions with alkenyl and aryl iodides. The application of these coupling reactions to the synthesis of biazulenes, terazulene 101, and related oligoazulenes is described, as well as the preparation of the azulenyl amino acid
Modulating structure and properties in organic chromophores: influence of azulene as a building block
作者:Masahito Murai、Sung-Yu Ku、Neil D. Treat、Maxwell J. Robb、Michael L. Chabinyc、Craig J. Hawker
DOI:10.1039/c4sc01623h
日期:——
The properties of isomeric azulene derivatives, substituted through the 5-membered ring, were examined using a combination of experimentation and theoretical calculations for a series of well-defined electroactive oligomers.