1192159-78-6Relevant academic research and scientific papers
Gold-catalyzed cycloisomerization of pyridine-bridged 1,8-diynes: An expedient access to luminescent cycl[3.2.2]azines
Chintawar, Chetan C.,Mane, Manoj V.,Tathe, Akash G.,Biswas, Suprakash,Patil, Nitin T.
supporting information, p. 7109 - 7113 (2019/09/30)
Gold-catalyzed diyne cycloisomerizations involving carbene/alkyne metathesis have been the focal point of attention for the past few years as it offers great potential to build complex polycyclic architectures. However, the design of novel cycloisomerizations has been mostly limited to 1,5/1,6-diynes and has remained very challenging to apply for higher 1,n-diynes. Herein, we disclose an unprecedented cycloisomerization of pyridine-bridged 1,8-diynes involving carbene/alkyne metathesis to access luminescent cycl[3.2.2]azines.
A new class of N-doped ionic PAHs: Via intramolecular [4+2]-cycloaddition between arylpyridines and alkynes
Mule, Ravindra D.,Shaikh, Aslam C.,Gade, Amol B.,Patil, Nitin T.
supporting information, p. 11909 - 11912 (2018/11/10)
Reported herein, for the first time, is a copper-promoted intramolecular [4+2]-cycloaddition cascade to access ionic N-doped polycyclic aromatic hydrocarbons (PAHs) with tunable emission wavelengths. It is shown that the reaction can be made catalytic with respect to Cu(OTf)2 when an external oxidant, Selectfluor, was used.
Oxidative Intramolecular 1,2-Amino-Oxygenation of Alkynes under AuI/AuIIICatalysis: Discovery of a Pyridinium-Oxazole Dyad as an Ionic Fluorophore
Shaikh, Aslam C.,Ranade, Dnyanesh S.,Rajamohanan, Pattuparambil R.,Kulkarni, Prasad P.,Patil, Nitin T.
supporting information, p. 757 - 761 (2017/01/14)
Oxidative intramolecular 1,2-amino-oxygenation reactions, combining gold(I)/gold(III) catalysis, is reported. The reaction provides efficient access to a structurally unique ionic pyridinium-oxazole dyad with tunable emission wavelengths. The application of these fluorophores as potential biomarkers has been investigated.
The intramolecular 5-: Exo, 7- endo -dig transition metal-free cyclization sequence of (2-alkynylphenyl) benzyl ethers: Synthesis of seven-membered fused benzo [b] furans
Gai, Rafaela,Do Carmo Pinheiro, Roberto,Neto, José S. S.,Iglesias, Bernardo A.,Acunha, Thiago V.,Back, Davi F.,Zeni, Gilson
, p. 6648 - 6658 (2018/06/08)
Base-promoted cyclization of (2-alkynylphenyl) benzyl ethers was studied in detail. The effects of the solvent, base, temperature, reaction time and amount of base on the efficacy of the cyclization reaction were analyzed and a new base-solvent system (tert-BuOK/DMSO) for effective cyclization of (2-alkynylphenyl) benzyl ethers was reported. The results showed that the cyclization reactions proceeded cleanly and smoothly under mild reaction conditions, employing tert-BuOK as a base, and DMSO as a solvent, at room temperature in a short reaction time (1 h). Under these conditions, a number of different substituted (2-alkynylphenyl) benzyl ethers were cyclized to the corresponding fused heterocycle cyclohepta[b]furans. This one-pot, two-step procedure occurred regioselectively giving only the cyclohepta[b]furans as the unique regioisomers via an initial intramolecular 5-exo-dig mode followed by an intramolecular 7-endo-dig mode. The cyclohepta[b]furan derivatives absorbed in the UV region (300-350 nm range) with molar absorptivity coefficient values attributed to spin and symmetry allowed π-π? electronic transitions. An emission located in the purple region (380-440 nm range), with a Stokes shift between 65-100 nm is probably associated with the charge transfer character of the excited state. The electrochemical analysis (CV) of the cyclohepta[b]furans showed an oxidation and reduction process, probably due to the presence of the selenium atom and π-anion radical species.
Copper-catalyzed tandem synthesis of indolo-, pyrrolo[2,1-a]isoquinolines, naphthyridines and bisindolo/pyrrolo[2,1-a]isoquinolines via hydroamination of ortho-haloarylalkynes followed by C-2 arylation
Verma, Akhilesh K.,Jha, Rajeev R.,Chaudhary, Ritu,Tiwari, Rakesh K.,Reddy, Kotla Siva K.,Danodia, Abhinandan
, p. 8191 - 8205,15 (2020/10/15)
An efficient approach for the copper-catalyzed regioselective tandem synthesis of diversely substituted indolo[2,1-a]isoquinolines 11a-r, pyrrolo[2,1-a]isoquinolines 12a-d, and indolo-, pyrrolo[2,1-f ][1,6]naphthyridines 14a-f via preferential addition of the heterocyclic amines onto the ortho-haloarylalkynes over N-arylation followed by intramolecular C-2 arylation is described. The scope of the developed chemistry was successfully extended for the direct synthesis of bisindolo-, pyrrolo[2,1-a]isoquinolines 15a-g, a regioisomer of the bisindolo[1,2-a]quinolines used as organic single-crystal field-effect transistor. Hydroxymethyl benzotriazole, which is an inexpensive and air stable compound, has been used as a ligand to carry out this onestep conversion of simple, readily available starting materials into an interesting class of heterocyclic compounds.
