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We communicate two mild, solvent-free mechanochemical coupling transformations of CF3 group with nitro compounds into amides or Schiff bases employing Ytterbia as a catalyst. This process proceeds via C−F bond activation, accompanied with utilisation of Si-based reductants/oxygen scavengers – reductants of the nitro group. The scope and limitations of the disclosed methodologies are thoroughly studied. To the best of our knowledge, this work is the first example of mechanical energy promoted transformation of the inert CF3 group into other functionalities. (Figure presented.). This research project was supported by a grant from National Science Centre (NSC) Poland, the SONATA 10 (Nr. 2015/19/D/ST5/02774) obtained by Dr. Viktor Iaroshenko. The salary of Dr. Satenik Mkrtchyan was covered by a grant from National Science Centre (NSC) Poland within the framework of European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement Nr. 665778 (POLONEZ 2 grant, Nr. 2016/21/P/ST5/00630). Professor Michael Pittelkow appreciates the support from the Danish Council for Independent Research (DFF 4181-00206 and 9040-00265) and from the University of Copenhagen.

Three dimensional (3D) acceptor‐donor‐acceptor (A−D‐A) type small molecules (M1, M2, M3 and M4) are theoretically investigated for optoelectronic properties. The designed molecules contain spirobif ...

Six Acceptor-Donor-Acceptor (A-D-A) types molecules with dimethyl dithieno[3, 2-b:2',3'-d]silole) -2,6-diyl (DTS) (M-1-M-3) and dimethyl cyclopenta [2, 1-b;3,4-b]-dithiophene (CPDT) (M-4-M-6) core ...

5,7-Dihydropyrido[3,2-b:5,6-b′]diindoles were prepared by a highly efficient two-step synthesis that involved a site-selective Suzuki coupling reaction of 2,3,5,6-tetrabromopyridine and a subsequent Pd-catalyzed cyclization that proceeded through a twofold C–N coupling reaction with aromatic and aliphatic amines. With the exception of the parent molecule, which was described in a patent without any characterization data, the 5,7-dihydropyrido[3,2-b:5,6-b′]diindoles are a new chemical entity. Their electrochemical and photochemical properties were investigated. These pyridodiindoles show promising fluorescence properties with good quantum yields and interesting electrochemical behavior. The optical and electronical properties were analyzed and explained by using DFT calculations.

The aromaticities of azines relative to benzene have been estimated by fusion with 15,16-dimethyldihydropyrene. Chemical shift data for the azine-fused dihydropyrenes (calculated at GIAO HF/6-31G*//B3LYP/6-31 + G*) were used to estimate the reduction in the dihydropyrene nucleus aromaticity. Choice of the saturated reference model was quite crucial in reliable estimation of aromaticity. Reference models with partial unsaturation at azine (21,23,25–32) gave better estimate of aromaticity than the parent dimethyldihydropyrene. Aromaticities of azines through chemical shift data and geometric parameter analysis were found to be 90–100% to that of benzene, highly consistent with the aromaticity estimation by nucleus independent chemical shift(0)πzz calculations. Copyright © 2014 John Wiley & Sons, Ltd.

The first zinc-catalyzed oxidative amidation of benzyl alcohols has been developed. Both aliphatic and aromatic amines can be tolerated and applied in this reaction. Various amides were prepared in good yields under solvent-free and mild conditions.

Functionalized indolizines were prepared by Lewis acid-catalyzed cyclizations of 3-(pyridin-2-yl)-propiolates with enones. This new type of reaction provides a convenient and regioselective approach to ester-substituted indolizine derivatives which are not readily available by other methods. Based on density function theory (DFT) calculations, a mechanism of the reaction has been suggested.

5,7-Dihydropyrido[3,2-b:5,6-b′]diindoles were prepared by a highly efficient two-step synthesis that involved a site-selective Suzuki coupling reaction of 2,3,5,6-tetrabromopyridine and a subsequent Pd-catalyzed cyclization that proceeded through a twofold C–N coupling reaction with aromatic and aliphatic amines. With the exception of the parent molecule, which was described in a patent without any characterization data, the 5,7-dihydropyrido[3,2-b:5,6-b′]diindoles are a new chemical entity. Their electrochemical and photochemical properties were investigated. These pyridodiindoles show promising fluorescence properties with good quantum yields and interesting electrochemical behavior. The optical and electronical properties were analyzed and explained by using DFT calculations.

Four Donor-Acceptor-Donor (D-A-D) type of donor molecules (M1-M4) with triphenylamine (TPA) as donor moiety, thiophene as bridge, and thiazolothiazole as acceptor unit were designed and its photovo ...

A series of indolo[2,3-b]quinoxaline derivatives were efficiently synthesized from 2,3-dibromoquinoxaline by two pathways. A one-pot approach using Pd-catalyzed two-fold C–N coupling and C–H activation reactions gave indolo[2,3-b]quinoxaline derivatives in good yields, but with limited substrate scope. In addition, a two-step approach to indolo[2,3-b]quinoxalines was developed which is based on Pd-catalyzed Suzuki coupling reactions and subsequent annulation by Pd-catalyzed two-fold C–N coupling with aromatic and aliphatic amines. The electrochemical and photochemical properties of indolo[2,3-b]quinoxaline derivatives were investigated. These studies show that 6-(4-methoxyphenyl)-6H-indolo[2,3-b]quinoxaline showed the highest HOMO energy level and lowest band gap.

The first zinc-catalyzed oxidative amidation of benzyl alcohols has been developed. Both aliphatic and aromatic amines can be tolerated and applied in this reaction. Various amides were prepared in good yields under solvent-free and mild conditions.

Trifluoromethyl-substituted 1,3-diketones can undergo direct alkynylation reactions which are not possible for alkyl- or aryl-substituted derivatives. The products can be easily transformed into 2,6-diaryl-4-trifluoromethylpyridines by acid-mediated [5+1] cyclization with urea. The reaction was thoroughly optimized by variation of the conditions and the scope was studied in detail. The products are not readily available by other methods. A plausible mechanism was suggested based on DFT calculations.

Benzofuroquinolines and furoquinolines are prepared in one-step from 2-alkynyl-3-bromobenzofurans and 2-alkynyl-3-bromofurans and electron-rich anilines, respectively, by a Pd-catalyzed domino C—N coupling/annulation process.

Functionalized indolizines were prepared by Lewis acid-catalyzed cyclizations of 3-(pyridin-2-yl)-propiolates with enones. This new type of reaction provides a convenient and regioselective approach to ester-substituted indolizine derivatives which are not readily available by other methods. Based on density function theory (DFT) calculations, a mechanism of the reaction has been suggested.

Trifluoromethyl-substituted 1,3-diketones can undergo direct alkynylation reactions which are not possible for alkyl- or aryl-substituted derivatives. The products can be easily transformed into 2,6-diaryl-4-trifluoromethylpyridines by acid-mediated [5+1] cyclization with urea. The reaction was thoroughly optimized by variation of the conditions and the scope was studied in detail. The products are not readily available by other methods. A plausible mechanism was suggested based on DFT calculations.