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Three new unsymmetrical thiophene-functionalized bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) donors (1-3) have been synthesized, characterised and examined as semiconducting materials for organic field-effect transistor (OFET) devices. The X-ray crystal structures of (1) and (2) reveal both neutral donors pack as dimers with lateral S⋯S contacts. For (1) the molecules are co-facially stacked in a head-to-tail manner with some degree of latitudinal slippage. A device prepared from a crystalline thin film of (1) deposited on unmodified silicon wafer substrate displays a mobility of 5.9 x 10-3 cm² V-1 s-1 with an on/off ratio of 11. The shorter CH2 linker in (2) results in poorer orbital overlap, likely due to significant longitudinal and latitudinal slippage between molecules in the crystal lattice. As a consequence, no field-effect response was observed for the device fabricated from (2). [ABSTRACT FROM AUTHOR]

The targeted replacement of acetate groups in the optically inactive [MnIII3O(O2CMe)3(mpko)3](ClO4) single-molecule magnet with their naphthalene, anthracene, and pyrene fluorescent analogues has led to three new emissive SMMs with enhanced photo-luminescence properties and potential applications in the field of molecular electronics. [ABSTRACT FROM AUTHOR]

The first application of 1-methyl-1H-pyrrole-2-carbaldehyde oxime as a ligand for the coordination of paramagnetic transition metal ions has afforded a new {MnIII25} barrel-like cluster linked via Na+ cations into a 1D polymeric topology that exhibits single-molecule magnetic behaviour. [ABSTRACT FROM AUTHOR]

The germylone dimNHCGe (5, dimNHC=diimino N‐heterocyclic carbene) undergoes a [2+2] cycloaddition with isocyanates RNCO (R=4‐tolyl or 3,5‐xylyl) to furnish novel alkyl carboxamido germylenes 7 (R=4‐tolyl) and 8 (R=3,5‐xylyl), featuring a C−C bond between the former carbene carbon and the isocyanate moiety. Heating a mixture of 8 with 4‐tolyl isocyanate to 100 °C results in isocyanate metathesis, demonstrating reversible C−C bond formation on the reduced germanium compound. DFT calculations suggest that this process occurs via the reductive dissociation of isocyanate from 8 that regenerates the parent Ge(0) compound 5. [ABSTRACT FROM AUTHOR]

An unsymmetrical guanidine‐cyclopropenimine proton sponge DAGUN and the related BF2‐chelate DAGBO are reported. Insight into the structural, electronic, bonding and photophysical properties of these two molecules are presented. Joint experimental and theoretical studies reveal the protonated form of DAGUN possesses an intramolecular N⋅⋅⋅H−N hydrogen bond which affords a high experimental pKBH+ of 26.6 (computed=26.3). Photophysical studies show that in solution DAGUN displays a green emission at 534 nm, with a large Stokes shift of 235 nm (14,718 cm−1). In contrast, the conjugate acid DAGUN‐H+ is only weakly emissive due to attenuated intramolecular charge transfer. X‐ray diffraction studies reveal that DAGBO contains a stable tetracoordinate boronium cation, reminiscent of the well‐established BODIPY family of dyes. In solution, DAGBO exhibits a strong blue emission at 450 nm coupled with a large Stokes shift (Δλ=158 nm, Δν=11,957 cm−1) and quantum yield of 62 %, upon excitation at 293 nm. DAGBO sets the stage as the first entry into a new class of boron‐difluoride diaminonaphthalenes (BOFDANs) that represent highly fluorescent and tunable next‐generation dyes with future promise for biosensing and bioimaging applications. [ABSTRACT FROM AUTHOR]

Reaction of NacNacGa with phenylisocyante generates a transient species amenable to unusual 1,3-C–H bond addition of unactivated sp3 C–H and sp2 C–H bonds of substrates featuring a hard donor atom. This reaction proceeds for pyridine oxide, dimethylsulfoxide, and dimethylacetamide, but not for pyridine, cyclohexanone, and ethyl acetate. C–H activation was also not observed for reactions with triethylphosphine oxide but, interestingly, in the presence of this compound isocyanate undergoes self-coupling on Ga(I) with a regioselectivity that is different when carried out in the absence of Et3PO. [ABSTRACT FROM AUTHOR]

A linear Cu 4 complex containing a combination of square pyramidal and octahedrally coordinated Cu(II) ions is reported. The metal centres are linked via diazine and chloride bridges. Magnetic studies reveal the presence of strong antiferromagnetic interactions via the diazine bridge and moderate ferromagnetic interactions via the chloro bridges. The pyrimidinyl hydrazone ligand O C{NHN C(Me)(pm)} 2 (pm = 2-pyrimidinyl) (L 3 H 2) has two potentially protic H atoms and multiple donor atoms. The reaction of L 3 H 2 with CuCl 2 ·2H 2 O yielded the tetranuclear complex [Cu 4 (L 3 H) 2 Cl 6 (CH 3 OH) 2 ] (1). Structural studies on 1 reveal the molecule is located about a crystallographic inversion centre, affording two crystallographically independent Cu(II) centres with the two symmetry equivalent [Cu 2 (L 3 H)Cl 3 CH 3 OH] units connected via µ 2 -Cl bridges to generate a linear tetranuclear copper complex. The ligand is singly deprotonated (L 3 H−) and twisted around the diazine N N′ bond, affording an N 3 donor set for the Cu1 centre and an N 2 O donor set for the Cu2 centre. The Cu1 ion is five coordinate with an [N 3 ] donor set from the L 3 H− ligand and the remaining two sites occupied by Cl− anions. The Cu2 ion is six coordinate with the L 3 H− ligand offering a mer [N 2 O] donor set, with the three remaining sites occupied by two Cl− anions and a MeOH molecule. Magnetic studies reveal the presence of strong antiferromagnetic interactions via the diazine bridge linking the Cu1 and Cu2 ions and moderate ferromagnetic interactions via the chloro bridges located about the inversion centre, connecting the Cu2 and Cu2i ions. [ABSTRACT FROM AUTHOR]

Review: 141 refs. [ABSTRACT FROM AUTHOR]

Cover Feature: Base-Stabilized Phosphinidene Oxide, Imide and Sulfide (Chem. Eur. J. 59/2023) Iminophosphorane, phosphinidene, phosphinidene imide, phosphinidene oxide, phosphinidene sulfide Keywords: Iminophosphorane; phosphinidene; phosphinidene imide; phosphinidene oxide; phosphinidene sulfide EN Iminophosphorane phosphinidene phosphinidene imide phosphinidene oxide phosphinidene sulfide 1 1 1 10/26/23 20231023 NES 231023 B Phosphinidene conducts an auction for the best P=X bond b : Cyclic phosphinoamidinate-supported phosphinidene (NP)P is a natural precursor to base-stabilized P SP III sp compounds (NP)P=X (X=O, NR, S). [Extracted from the article]

The germylone dimNHCGe (dimNHC=diimino N‐heterocyclic carbene) reacts with azides N3R (R=SiMe3 or p‐tolyl) to furnish the first examples of germanium π‐complexes, i. e. guanidine‐ligated compounds (dimNHI−SiMe3)Ge (NHI=N‐heterocyclic imine, R=SiMe3) and (dimNHI−Tol)Ge (R=p‐tolyl). DFT calculations suggest that these species are formed by a Staudinger type replacement of dinitrogen in the azide by a nucleophilic germylone, leading to a transient carbene adduct of iminogermylidene. Heating a solution of compound (dimNHI−SiMe3)Ge to 70 °C results in extrusion of the iminogermylidene that further aggregates to produce the known [Me3SiNGe]4 tetramer, whereas the imidazolylidene fragment transforms into an unusual heptatriene species that can be considered as a product of carbene insertion into the C−C bond of a pendant Ar substituent at the imidazolylidene nitrogen of the dimNHC. Reaction of (dimNHI−SiMe3)Ge with tetrachloro‐o‐benzoquinone results in the net transfer of a germanium atom and formation of the free diimino‐guanidine ligand. This ligand also forms when (dimNHI−SiMe3)Ge is treated with azide N3(p−Tol), with the germanium product being [(p−Tol)NGe]n [ABSTRACT FROM AUTHOR]

Diimino−carbene‐supported germylone dimNHCGe does not react with BPh3 and does not activate dihydrogen in the FLP mode in the combination with this borane. However, it reacts with B(C6F5)3 to give the zwitterionic borate dimNHCGe−(C6F4)BF(C6F5)2. This compound can be converted into the hydroborate dimNHCGe−(C6F4)BH(C6F5)2 (8) and further into [dimNHCGe−(C6F4)B(C6F5)2]+ (4). Compound 4 is a Ge/B analogue of Stephan's FLP parent P/B compound (C6H2Me3)2P−C6F4−B(C6F5)2 but unlike the latter cannot split dihydrogen. Moreover, attempts to prepare a Ge/B analogue of the zwitterion (C6H2Me3)2HP−C6F4−BH(C6F5)2 by protonation of borate 8 resulted in immediate elimination of H2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Syntheses of a series of dibromo- and diiodo-BODIPY derivatives. • Compared photostability and photosensitization efficiency of BODIPY derivatives. • Antibacterial activity against B. subtilis by BODIPY containing tertiary amine. A series of 2,6-dibromo-, 2,6-diiodo-4,4-difluoro-4-bora-3a,4a-diaza- s -indacene, together with the 4,4-dicyano analogs were synthesized. The photostability of these BODIPY derivatives and their efficiencies in generating singlet oxygen species were determined. Among these, 2,6-dibromo-4,4-dicyano-4-bora-3a,4a-diaza- s -indacene (BODIPY 6) was found to be similarly photostable as Rose Bengal, while 2,6-diiodo-8-iodomethyl-1,3,5,7-tetramethyl-4,4-difluoro-4-bora-3a,4a-diaza- s -indacene (BODIPY 10) and 1,3,5,7,8-pentamethyl-2,6-diiodo-4,4-dicyano-4-bora-3a,4a-diaza- s -indacene (BODIPY 5) were found to be the least stable. For the ability to generate singlet oxygen species, 2,6-dibromo- (BODIPY 3) and 2,6-diiodo-4,4-difluoro-4-bora-3a,4a-diaza- s -indacene (BODIPY 2) were found to be more efficient than Rose Bengal, while BODIPY 10 and 1,3,5,7,8-pentamethyl-2,6-diiodo-4,4-dicyano-4-bora-3a,4a-diaza- s -indacene (BODIPY 5) were quite poor photosensitizers. When Bacillus subtilus cultures were supplemented with the photosensitizers and exposed to light, it was found that the presence of a positive charge in the photosensitizers was essential in order for them to be effective bacterialcidal agents. [ABSTRACT FROM AUTHOR]

A series of imino-POCNR, amino-POCNR2, and bis(phosphinite) POCOP pincer complexes of Ni(II) were prepared and tested in catalytic deoxygenative hydroboration of amides with HBPin to the corresponding amines. In contrast to the deoxygenative hydrosilylation approach, primarily developed for tertiary amides, superior reactivity in Ni-catalyzed deoxygenative hydroboration was demonstrated for secondary carboxamides. The bis(phosphinite) hydride complex (POCOP)NiH proved the most active in these reactions, tolerating potentially reducible functionalities such as internal alkenes, esters, nitriles, heteroaromatic compounds, and tertiary amides. Preferable hydroboration of secondary amides was also demonstrated in the presence of primary amide functionalities. The reactions were conducted at 60–80 °C, representing a rare example of a base-metal catalytic system for selective deoxygenation of secondary amides to the corresponding amines under mild conditions. In contrast to secondary amides, deoxygenative hydroboration of primary amides was demonstrated using an iminophosphinite pre-catalyst (POCNDmp)Ni(CH2TMS) (Dmp = 2,6-Me2C6H3). Deoxygenation reactions were suggested to proceed via a direct C–O bond cleavage mechanism, which is triggered by dehydrogenative N-borylation to access more electrophilic N-borylamides amenable to the addition of HBPin to the carbonyl group. [ABSTRACT FROM AUTHOR]

A new asymmetrically substituted ONOO Schiff base ligand N-(2′-hydroxy-1′-naphthylidene)-3-amino-2-naphthoic acid (nancH2) was prepared from the condensation of 2–hydroxy–1–naphthaldehyde and 3–amino–2–naphthoic acid. nancH2 reacts with Cu2(O2CMe)4·2H2O in the presence of Gd(O2CMe)3·6H2O to afford a uniform one-dimensional homometallic chain, [CuII(nanc)]n (1). The structure of 1 was elucidated via single crystal X-ray diffraction studies, which revealed that the Cu(II) ions adopt distorted square planar geometries and are coordinated in a tridentate manner by an [ONO] donor set from one nanc2− ligand and an O− of a bridging carboxylate group from a second ligand. The bridging carboxylato group of the nanc2− ligand adopts a syn, anti-η1:η1:μ conformation linking neighboring Cu(II) ions, forming a 1D chain. The magnetic susceptibility of 1 follows Curie–Weiss law in the range 45–300 K (C = 0.474(1) emu K mol-1, θ = +7.9(3) K), consistent with ferromagnetic interactions between S = ½ Cu(II) ions with g = 2.248. Subsequently, the data fit well to the 1D quantum Heisenberg ferromagnetic (QHFM) chain model with g = 2.271, and J = +12.3 K. DFT calculations, implementing the broken symmetry approach, were also carried out on a model dimeric unit extracted from the polymeric chain structure. The calculated exchange coupling via the carboxylate bridge (J = +13.8 K) is consistent with the observed ferromagnetic exchange between neighbouring Cu(II) centres. [ABSTRACT FROM AUTHOR]

Keywords: chlorosilanes; disilylenes; insertion; tetrelenes EN chlorosilanes disilylenes insertion tetrelenes 1 1 1 12/20/22 20221215 NES 221215 B Insertion of silylene b : SiCl SB 2 sb into the Si-Si bond of a phosphinoamidinate-supported disilylene affords a SiCl SB 2 sb -bridged bis(silylene) that, upon heating, rearranges into a silyl-substituted disilylene. More information can be found in the Research Article by S. F. Vyboishchikov, G. I. Nikonov and co-workers (DOI: 10.1002/chem.202202799). Front Cover: The Insertion of EII and EIV Chlorides (E=Si, Ge) into the Si-Si Bond of Disilylene (Chem. Eur. J. 70/2022). [Extracted from the article]

A 1,1'‐disubstituted ferrocenyl pyrroloimidazolone with syn stereochemistry undergoes double lithiation–electrophile quench in a one‐pot procedure to give C2‐symmetric 1,1',2,2'‐tetrasubstituted products in >95 : 5 diastereomeric ratio (dr). These results represent an extension of double lithiation to access tetrasubstituted planar chiral ferrocenes for the first time to a nitrogen‐linked (pyrroloimidazolone) chiral directing group. The stereochemistry of the products was determined by X‐ray crystallography of distannane and dibromide adducts in combination with deuteration, elimination, and transmetalation experiments. Results support that products arise from selective deprotonation of the pro‐Sp position of each cyclopentadienyl (Cp) ring. [ABSTRACT FROM AUTHOR]

In recent years, the dramatic increase in power conversion efficiency (PCE) coupled with a decrease in the total cost of third-generation solar cells has led to a significant increase in the collaborative research efforts of academic and industrial researchers. Such interdisciplinary studies have afforded novel materials, which in many cases are now ready to be brought to the marketplace. Within this framework, the field of perovskite solar cells (PSCs) is currently an important area of research due to their extraordinary light-harvesting properties. In particular, PSCs prepared via facile synthetic procedures, containing hole transport materials (HTMs) with versatile triphenylamine (TPA) structural cores, amenable to functionalization, have become a focus of intense global research activity. To optimize the efficiency of the solar cells to achieve efficiencies closer to rival silicon-based technology, TPA building blocks must exhibit favourable electrochemical, photophysical, and photochemical properties that can be chemically tuned in a rational manner. Although PSCs based on TPA building blocks exhibit attractive properties such as high-power efficiencies, a reduction in their synthetic costs coupled with higher stabilities and environmental considerations still need to be addressed. Considering the above, a detailed summary of the most promising compounds and current methodologies employed to overcome the remaining challenges in this field is provided. The objective of this review is to provide guidance to readers on exploring new avenues for the discovery of efficient TPA derivatives, to aid in the future development and advancement of TPA-based PSCs for commercial applications. [ABSTRACT FROM AUTHOR]

Reaction of NacNacGa with azide N3SiMe3 results in the generation of a transient imide NacNacGa(＝NSiMe3) that can cleave unactivated sp3 C–H and sp2 C–H bonds of different substrates, affording gallium amides. Pyridine, cyclohexanone, ethyl acetate, DMSO, and triethylphosphine oxide were activated in this process producing corresponding gallium amides. All new compounds were characterised by multinuclear NMR and X-ray diffraction. [ABSTRACT FROM AUTHOR]

Reaction of the Ga(I) compound NacNacGa (9) with the diazo compound N2CHSiMe3 affords the nitrilimine compound NacNacGa(N‐NCSiMe3)(CH2SiMe3) (10). Carrying out this reaction in the presence of pyridine does not lead to C−H activation on the transient alkylidene NacNacGa=CHSiMe3 but generates a metallated diazo species NacNacGa(NHN=CHSiMe3)(CN2SiMe3) (13) that further rearranges into the isonitrile compound NacNacGa(NHN=CHSiMe3)(N(NC)SiMe3) (15). Reactions of 10 with the silane H3SiPh and the borane HBcat furnished products of 1,3 addition to the nitrilimine moiety NacNacGa{N(ERn)NCSiMe3}(CH2SiMe3), whereas reaction with the diborane B2cat2 gave the product of formal nitrene insertion into the B−B bond. DFT calculations suggest that the interaction of 9 with N2CHSiMe3 proceeds through intermediate formation of an alkylidene compound that undergoes CH activation with a second molecule of N2CHSiMe3. Insertion into the B−B bond likely proceeds through an initial 1,3‐addition of the diborane, followed by boryl migration to the former nitrene center. [ABSTRACT FROM AUTHOR]

Carbon–carbon bonding forming reactions of two cyclic sulfate esters and a cyclic sulfamidate are reported, the former with lithium dianions to give substituted tetrahydrofuran derivatives with displacement of sulfate, and the latter undergoes ring-opening monosubstitution reactions with stabilised organolithiums and an organocuprate species. [Copyright &y& Elsevier]

An N‐propargyl pyrroloimidazolone with syn stereochemistry derived from L‐proline serves as a starting material for the diastereoselective synthesis (>95:5 dr) of propargyl alkynes or allenamides by direct quench of its lithiated intermediate with alkylating agents or aldehydes/ketones, respectively. Use of the epimeric anti pyrroloimidazolone starting material results in reversal of stereochemistry at the propargyl position in the products, without the need to prepare a separate substrate from D‐proline. Lithiation of the syn pyrroloimidazolone and quench with prochiral benzaldehydes without prior transmetalation gives allenamides with crystallographically verified atypical stereochemistry of the benzylic alcohol in >95:5 dr. The epimeric series of benzylic alcohols may also be obtained in >95:5 dr by employing transmetalation with chlorotitanium triisopropoxide prior to aldehyde quench. Density Functional Theory (DFT) computational studies provide a rationale for the change in benzylic alcohol stereochemistry by virtue of differing stereofacial attack in 6,5‐bicyclic (Li) or 6‐membered (Ti) transition states. [ABSTRACT FROM AUTHOR]

The development of near‐infrared (NIR) luminescent materials has emerged as a promising research field with important applications in solid‐state lighting (SSL), night‐vision‐readable displays, and the telecommunication industry. Over the past two decades, remarkable advances in the development of light‐emitting electrochemical cells (LECs) have stunned the SSL community, which has in turn driven the quest for new classes of stable, more efficient NIR emissive molecules. In this review, an overview of the state of the art in the field of near‐infrared light‐emitting electrochemical cells (NIR‐LEC) is provided based on three families of emissive compounds developed over the past 25 years: i) transition metal complexes, ii) ionic polymers, and iii) host–guest materials. In this context, ionic and conductive emitters are particularly attractive since their emission can be tuned via molecular design, which involves varying the chemical nature and substitution pattern of their ancillary ligands. Herein, the challenges and current limitations of the latter approach are highlighted, particularly with respect to developing NIR‐LECs with high external quantum efficiencies. Finally, useful guidelines for the discovery of new, efficient emitters for tailored NIR‐LEC applications are presented, together with an outlook towards the design of new NIR‐SSL materials. [ABSTRACT FROM AUTHOR]

The preparation of a series of 4,4′,5,5′-substituted benzo-fused 1,2,5,6-tetrathiocins X2C6H2S4C6H2X2 (1a–1g) were prepared from the reaction of S2Cl2 with 1,2-C6H4X2 (X = OMe, OEt; X2 = OCH2O, OCH2CH2O, OCH2CH2CH2O, MeNC(＝O)NMe, O(CH2CH2O)4). The oxidative addition of 1a–1g to zero-valent Pd2dba3 or Pt2dba3 (dba = dibenzylideneacetone) in the presence of bis (diphenylphosphino)ethane (dppe) resulted in formation of the substituted mononuclear benzenedithiolate complexes M(L)(dppe) [L = dithiolate ligand; 2a–2g (M = Pd) and 3a–3g (M = Pt)] in 37–89% yield based on recrystallized material. Representative examples of M(L)(dppf) [dppf = bis-diphenylphosphinoferrocene; 4a, 4g (M = Pd) and 5g (M = Pt)] were prepared in a similar fashion. The structures of all derivatives were determined by X-ray diffraction, multinuclear NMR and elemental analysis. The reactivity of the two crown ether dithiolate complexes, 2g and 4g, with 1 equivalent of NaBPh4 led to isolation of the 1 : 1 complexes in which the Na+ cation is bound in the macrocyclic crown, [Na(2g)(MeOH)2][BPh4] and [Na(4g)][BPh4] whose structures were determined by X-ray diffraction. Electrochemical studies supported through DFT calculations on the crown ether derivatives revealed a series of ligand-based oxidation waves corresponding to the dithiolate ligand (and dppf for 4g and 5g) whose redox potentials were shifted by ca. +0.1 V on binding to Na+. [ABSTRACT FROM AUTHOR]