Novel (E)-1-(aryl)-3-(4-(2-(dimethylamino)ethoxy)-3-methoxyphenyl) prop-2-en-1-ones 4 were synthesized by a Claisen-Schmidt reaction of 4-(2-(dimethylamino)ethoxy)-3-methoxy-benzaldehyde (2) with several acetophenone derivatives 3. Subsequently, cyclocondensation reactions of chalcones 4 with hydrazine hydrate afforded the new racemic 3-aryl-5-(4-(2-(dimethylamino)ethoxy)-3-methoxyphenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehydes 5 when the reaction was carried out in formic acid. The antifungal activity of both series of compounds against eight fungal species was determined. In general, chalcone derivatives 4 showed better activities than pyrazolines 5 against all tested fungi. None of the compounds 4a–g and 5a–g showed activity against the three Aspergillus spp. In contrast, most of the compounds 4 showed moderate to high activities against three dermatophytes (MICs 31.25–62.5 µg/mL), being 4a followed by 4c the most active structures. Interestingly, 4a and 4c possess fungicidal rather than fungistatic activities, with MFC values between 31.25 and 62.5 μg/mL. The comparison of the percentages of inhibition of C. neoformans by the most active compounds 4, allowed us to know the role played by the different substituents of the chalcones’ A-ring. Also the most anti-cryptococcal compounds 4a–c and 4g, were tested in a second panel of five clinical C. neoformans strains in order to have an overview of their inhibition capacity not only of standardized but also of clinical C. neoformans strains. DFT calculations showed that the electrophilicity is the main electronic property to explain the differences in antifungal activities for the synthesized chalcones and pyrazolines compounds. Furthermore, a quantitative reactivity analysis showed that electron-withdrawing substituted chalcones presented the higher electrophilic character and hence, the greater antifungal activities among compounds of series 4.

Three novel donor–π‐bridge–donor (D‐π‐D) hole‐transporting materials (HTMs) featuring triazatruxene electron‐donating units bridged by different 3,4‐ethylenedioxythiophene (EDOT) π‐conjugated linkers have been synthesized, characterized, and implemented in mesoporous perovskite solar cells (PSCs). The optoelectronic properties of the new dumbbell‐shaped derivatives (DTTXs) are highly influenced by the chemical structure of the EDOT‐based linker. Red‐shifted absorption and emission and a stronger donor ability were observed in passing from DTTX‐1 to DTTX‐2 due to the extended π‐conjugation. DTTX‐3 featured an intramolecular charge transfer between the external triazatruxene units and the azomethine–EDOT central scaffold, resulting in a more pronounced redshift. The three new derivatives have been tested in combination with the state‐of‐the‐art triple‐cation perovskite [(FAPbI3)0.87(MAPbBr3)0.13]0.92[CsPbI3]0.08 in standard mesoporous PSCs. Remarkable power conversion efficiencies of 17.48 % and 18.30 % were measured for DTTX‐1 and DTTX‐2, respectively, close to that measured for the benchmarking HTM spiro‐OMeTAD (18.92 %), under 100 mA cm−2 AM 1.5G solar illumination. PSCs with DTTX‐3 reached a PCE value of 12.68 %, which is attributed to the poorer film formation in comparison to DTTX‐1 and DTTX‐2. These PCE values are in perfect agreement with the conductivity and hole mobility values determined for the new compounds and spiro‐OMeTAD. Steady‐state photoluminescence further confirmed the potential of DTTX‐1 and DTTX‐2 for hole‐transport applications as an alternative to spiro‐OMeTAD.

Two novel and simple donor-π-bridge-donor (D-π-D) holetransporting materials (HTMs) containing two units of the pmethoxytriphenylamine (TPA) electron donor group covalently bridged by means of the 3,4-dimethoxyselenophene spacer through single and triple bonds are reported. The optoelectronic and thermal properties of the new selenium-containing HTMs have been determined using standard experimental techniques and theoretical density functional theory (DFT) calculations. The selenium-based HTMs have been incorporated in mesoporous perovskite solar cells (PSCs) in combination with the triple-cation perovskite [(FAPbI 3 ) 0.87 (MAPbBr 3 ) 0.13 ] 0.92 [CsPbI 3 ] 0.08 . Limited values of power conversion efficiencies, up to 13.4 %, in comparison with the archetype spiro-OMeTAD (17.8 %), were obtained. The reduced efficiencies showed by the new HTMs are attributed to their poor film-forming ability, which constrains their photovoltaic performance due to the appearance of structural defects (pinholes).

The third generation of photovoltaic technologies has attracted the attention of the scientific community since the groundbreaking report by Miyasaka and coworkers with the introduction of perovskite solar cells (PSCs). [1] In just a few years of development, PSCs have reached exceptional power conversion efficiencies (PCEs) passing from the initial 3.8% in 2009 to the recently certified 25.5%. [2] Organic-inorganic metal halide perovskites with the chemical formula ABX 3 (where A ¼ small organic cation, such as methylammonium (MA) or formamidinium (FA), B ¼ Pb 2þ , and X ¼ Br À or I À ) exhibit outstanding intrinsic properties, [3] including wide light absorption, [4] high charge-carrier mobilities, [5] long charge diffusion length, [6] and solution-processed fabrication, which can be precisely tuned through compositionally engineered modifications. [7][8][9][10] The ambipolar behavior showed by organic-inorganic perovskites enables their use in conventional and inverted architectures, where the perovskite is sandwiched between n-type and p-type charge-transporting layers. [11] Despite the great performances and simpler fabrication of planar devices, the most featured

Theoretical methods of the SOC-NEVPT2 type combined with a molecular fragmentation scheme have proven to be a powerful tool that allows explaining the luminescence sensitization mechanism in Ln (III) coordination...