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1.
Chemistry ; 28(70): e202202639, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36121335

RESUMO

Reactivity studies of the GeII →B complex L(Cl)Ge⋅BH3 (1; L=2-Et2 NCH2 -4,6-tBu2 -C6 H2 ) were performed to determine the effect on the GeII →B donation. N-coordinated compounds L(OtBu)Ge⋅BH3 (2) and [LGe⋅BH3 ]2 (3) were prepared. The possible tuning of the GeII →B interaction was proved experimentally, yielding compounds 1-PPh2 -8-(LGe)-C10 H6 (4) and L(Cl)Ge⋅GaCl3 (5) without a GeII →B interaction. In 5, an unprecedented GeII →Ga coordination was revealed. The experimental results were complemented by a theoretical study focusing on the bonding in 1-5. The different strength of the GeII →E (E=B, Ga) donation was evaluated by using energy decomposition analysis. The basicity of different L(X)Ge groups through proton affinity is also assessed.

2.
Chemistry ; 27(52): 13149-13160, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34096106

RESUMO

The titled 2,1-benzazaphosphole (1) (i. e. ArP, where Ar=2-(DippN=CH)C6 H4 , Dipp=2,6-iPr2 C6 H3 ) showed a spectacular reactivity behaving both as a reactive heterodiene in hetero-Diels-Alder (DA) reactions or as a hidden phosphinidene in the coordination toward selected transition metals (TMs). Thus, 1 reacts with electron-deficient alkynes RC≡CR (R=CO2 Me, C5 F4 N) giving 1-phospha-1,4-dihydro-iminonaphthalenes 2 and 3, that undergo hydrogen migration producing 1-phosphanaphthalenes 4 and 5. Compound 1 is also able to activate the C=C double bond in selected N-alkyl/aryl-maleimides RN(C(O)CH)2 (R=Me, tBu, Ph) resulting in the addition products 7-9 with bridged bicyclic [2.2.1] structures. The binding of the maleimides to 1 is semi-reversible upon heating. By contrast, when 1 was treated with selected TM complexes, it serves as a 4e donor bridging two TMs thus producing complexes [µ-ArP(AuCl)2 ] (10), [(µ-ArP)4 Ag4 ][X]4 (X=BF4 (11), OTf (12)) and [µ-ArP(Co2 (CO)6 )] (13). The structure and electron distribution of the starting material 1 as well as of other compounds were also studied from the theoretical point of view.

3.
Chemistry ; 27(52): 13096-13097, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34363422

RESUMO

Invited for the cover of this issue are Zoltán Benko, Libor Dostál and co-workers at the University of Pardubice and the Budapest University of Technology and Economics. The image depicts signs for the two different pathways representing the two differing reaction types which were clearly observed for 2,1-benzazaphosphole. Read the full text of the article at 10.1002/chem.202101686.

4.
Chemistry ; 27(59): 14577-14581, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34495561

RESUMO

The aryltellurenyl cation [2-(tBuNCH)C6 H4 Te]+ , a Lewis super acid, and the weakly coordinating carborane anion [CB11 H12 ]- , an extremely weak Brønsted acid (pKa =131.0 in MeCN), form an isolable ion pair complex [2-(tBuNCH)C6 H4 Te][CB11 H12 ], in which the Brønsted acidity (pKa 7.4 in MeCN) of the formally hydridic B-H bonds is dramatically increased by more than 120 orders of magnitude. The electrophilic activation of B-H bonds in the carborane moiety gives rise to a proton transfer from boron to nitrogen at slightly elevated temperatures, as rationalized by the isolation of a mixture of the zwitterionic isomers 12- and 7-[2-(tBuN{H}CH)C6 H4 Te(CB11 H11 )] in ratios ranging from 62 : 38 to 80 : 20.

5.
Chemistry ; 26(27): 6070-6075, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32092197

RESUMO

The reactions of monomeric C,N-chelated organogermanium(II) hydride L(H)Ge⋅BH3 with organolithium salts RLi yielded lithium hydrogermanatoborates (Li(THF)2 {BH3 [L(H)GeR]})2 . Compound (Li(THF)2 {BH3 [L(H)GePh]})2 was used as a source of LiH for the reduction of organic C=O or C=N bonds in nonpolar solvents accompanied by the elimination of a neutral complex L(Ph)Ge⋅BH3 . The interaction of (Li(THF)2 {BH3 [L(H)GePh]})2 with the polar C=O bond was further investigated by computational studies revealing a plausible geometry of a pre-reactive intermediate. The experimental and theoretical studies suggest that, although the Li atom of (Li(THF)2 {BH3 [L(H)GePh]})2 coordinates the C=O bond, the GeH fragment is the active species in the reduction reaction. Finally, benzaldehyde was reduced by a mixture of L(H)Ge⋅BH3 with PhLi in nonpolar solvents.

6.
Chemistry ; 26(5): 1144-1154, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31769071

RESUMO

Treatment of N,C,N-chelated organopnictogen(I) compounds ArE (1-3) (Ar=2,6-(RN=CH)2 C6 H3 , E/R=As/Dmp (1), Sb/tBu (2), and Bi/tBu (3), where Dmp=2,6-Me2 C6 H3 ) with various electron-deficient alkynes RC≡CR' (R/R'=CO2 Me (DMAD), R/R'=H/CO2 Me, or R/R'=NC5 F4 ) affords different types of heterocyclic compounds. In these reactions, 1-3 act as hidden dienes and participate in hetero-Diels-Alder (DA) reactions, a feature that has been only rarely reported for heavier pnictogen compounds. In this way, reactions of 1 furnished the set of 1-arsanaphthalenes 4-6. The most likely mechanism involves two steps, that is, an arsa-DA reaction giving a 1-arsa-1,4-dihydro-iminonaphthalene, followed by CH→NH proton migration. In contrast, this reaction sequence terminates at the first step in the case of the antimony analogue 2, thus giving the 1-stiba-1,4-dihydro-iminonaphthalenes 7 and 8. Reactions of the bismuth congener 3 gave one of two products depending on the alkyne used. Reaction of 3 with DMAD gave 1-bisma-1,4-dihydro-iminonaphthalene 9, whilst its reaction with two equivalents of HC≡C(CO2 Me) gave bismacyclohexadiene (10). All compounds have been characterized by NMR, IR, and Raman spectroscopies and X-ray diffraction analysis. The experimental data were complemented by a computational study, including a description of the reaction profiles of the hetero-DA reactions and an assessment of the aromaticities of the heterocyclic naphthalene derivatives.

7.
Chemistry ; 25(56): 12884-12888, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31353625

RESUMO

The reaction of N,C,N-chelated stibinidene ArSb (1) (Ar=C6 H3 -2,6-(CH=NtBu)2 ) with selected N-alkyl/aryl-maleimides RN(C(O)CH)2 (R=Me, tBu, Ph) gave the addition products with bridged bicyclic [2.2.1] structure containing an antimony atom at the bridgehead position, fused with a 6-membered benzene and a 5-membered N-alkyl/aryl-pyrrolidine ring. These compounds were completely characterized. More importantly, additional studies showed that these reactions are reversible in solution, thereby representing an unprecedented reversible activation of a C=C bond by an antimony(I) compound.

8.
Chemistry ; 25(22): 5668-5671, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30861223

RESUMO

The 2,1-benzazaarsole (1) showed a diene-like reactivity towards selected alkynes RC≡CR (R=CO2 Me, C5 F4 N) thus forming 1-arsa-1,4-dihydro-iminonaphthalenes 2 a and 3 a as hardly isolable intermediates, that underwent facile CH→NH proton migration leading to before elusive substituted 1-arsanaphthalenes 2 b and 3 b that could be completely structurally characterized.

9.
Chemistry ; 24(5): 1104-1111, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29057526

RESUMO

Studies are focused on the redox potentials of N→Sn coordinated distannnynes {L1-3 Sn}2 (L1 =1, L2 =2 and L3 =3, in which L1 is [C6 H3 -2,6-(Me2 NCH2 )2 ]- , L2 is [C6 H2 -2,4-tBu2 -6-(Et2 NCH2 )]- and L3 is [C6 H2 -2,4-tBu2 -6-(DippN=CH)]- ; Dipp=2,6-diisopropylphenyl), containing the tin atom in oxidation state +I. Distannynes 1-3 were used as ligands for transition metals, and complexes [{L1 Sn}2 ⋅Fe(CO)4 ] (4) and [{L2 Sn}2 ⋅Fe(CO)4 ] (5) were prepared. The set of N→Sn coordinated distannynes 1-5 was studied by cyclic voltammetry measurements and the oxidation potentials of tin atoms in 1-5 were determined. The redox potentials are influenced by either ligands L1-3 or SnI →Fe coordination. Oxidation reactions of 1-3 were also studied. The reaction of 2 with (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) provided mixed organotin oxide {(L2 SnO)(L2 )Sn(µ-O)}2 (6) as a consequence of the instability of the expected {L2 Sn⋅TEMPO} complex. To support this proposed mechanism, the N→Ge coordinated digermyne {L2 Ge}2 (7) was prepared. The reaction of 7 with TEMPO provided the expected complex {L2 Ge⋅TEMPO} (8).

10.
Chemistry ; 24(54): 14470-14476, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30016544

RESUMO

Studies have been focused on the synthesis of N→Ga-coordinated organogallium selenides and tellurides [L1 Ga(µ-Se)]2 (1), [L2 Ga(µ-Se)]2 (2) and [L1 Ga(µ-Te)]2 (3), respectively, containing either N,C,N- or C,N-chelating ligands L1, 2 (L1 is {2,6-(Me2 NCH2 )2 C6 H3 }- and L2 is {2-(Et2 NCH2 )-4,6-tBu2 -C6 H2 }- ) having Ga/E (E=Se or Te) atoms in 1/1 ratio. To change the Ga/E ratio, an unusual N→Ga-coordinated organogallium tetraselenide L1 Ga(κ2 -Se4 ) (4) was prepared. An unprecedented complex (L1 Ga)2 (µ-Te2 )(µ-Te) (5), as the result of the non-stability of 3, was also isolated. Compound 2 is a suitable single-source precursor for the preparation of amorphous GaSe thin films by the spin coating. Moreover, simple heating of an octadecylamine solution of 2 provided, after work up, monoclinic Ga2 Se3 crystals with different crystallinity according to conditions used. Therefore, compound 2 may be also used as a source of Ga2 Se3 in the low-temperature doping process of Bi2 Se3 .

11.
Chemistry ; 23(10): 2340-2349, 2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-27943507

RESUMO

The reduction of N,C,N-chelated antimony(III) chlorides [C6 H3 -2,6-(CH=NR)2 ]SbCl2 (R=Ph (1), tBu (2), Dip (3); Dip=2,6-iPr2 C6 H3 ) with an appropriate amount of KC8 or Li[AlH4 ] resulted in the formation of rare examples of monomeric stibinidenes [C6 H3 -2,6-(CH=NR)2 ]Sb (R=Ph (4), tBu (5), Dip (6)). Similarly, the reduction of compounds 1 or 2 by two equivalents of K[B(sBu)3 H] led to the stibinidenes 4 and 5. In contrast, the analogous reaction of compound 3 resulted in the formation of an unprecedented stibinidene [C6 H3 -2-(CH=NR)-6-(CH2 NHR)]Sb (7) (R=Dip), in which the hydrogen atoms that come from the K[B(sBu)3 H] are incorporated into the ligand backbone. To gain further insight into this intriguing reactivity with K[B(sBu)3 H] and to assess the influence of the substitution at both the antimony atom and pendant substituents, we prepared compounds [C6 H3 -2-(CH=NDip)]Sb(Ph)Cl (8) and [C6 H2 -2-(CH=NDip)-4,6-(tBu)2 ]SbCl2 (9). The treatment of compound 8 with K[B(sBu)3 H] smoothly led to the 1-Ph-2-Dip-1H-2,1-benzazastibole (11), whereas the reaction of compound 9 with K[B(sBu)3 H] resulted in either tBu-substituted 1-Cl-2-Dip-1H-2,1-benzazastibole (13) or the formation of unprecedented Sb-Sb dimer bis(2-Dip-1H-2,1-benzazastibole) (12) depending on the reaction stoichiometry. The miscellaneous reactivity of antimony(III) precursors with reducing agents together with the structure and bonding of the resulting products has also been investigated from a theoretical point of view.

12.
Chemistry ; 23(13): 3074-3083, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28052458

RESUMO

Treatment of the neutral pyridine-based ligands L1 -L3 , bearing either one or two RN=CH imine moieties {where L1 and L2 are N,N-chelating ligands 2-(RN=CH)C5 H4 N (R=Ph (L1 ) or R=2,4,6-Ph3 C6 H2 (L2 )) and L3 is the N,N,N-chelating ligand 2,6-(RN=CH)2 C5 H3 N (R=2,6-iPr2 C6 H3 )}, with HSiCl3 yielded N→Si-coordinated silicon(IV) amides 2-{Cl3 SiN(R)CH2 }C5 H4 N (1, R=Ph; 2, R=2,4,6-Ph3 C6 H2 ) and 2-{Cl3 SiN(R)CH2 }-6-(RN=CH)C5 H4 N (3, R=2,6-iPr2 C6 H3 ). The organosilicon amides 1-3 are the products of spontaneous hydrosilylation of the RN=CH imine moiety induced by N→Si coordination of the proposed N,N-chelated chlorosilanes L1 →SiHCl3 (1 a), L2 →SiHCl3 (2 a), and L3 →SiHCl3 (3 a). Furthermore, the reaction of L3 with an excess of HSiCl3 provided the intramolecularly coordinated chlorosilicon diamide cyclo-{(C5 H3 N)-1,3-(CH2 NR)2 }SiCl2 (4) (R=2,6-iPr2 C6 H3 ) as the product of spontaneous reduction of both RN=CH imine moieties. The compounds have been characterized by NMR spectroscopy (1-4) and single-crystal X-ray diffraction analysis (1, 3, and 4). The mechanism of the hydrosilylation of the second RN=CH imine moiety in 3 by an excess of SiHCl3 has also been studied. The experimental work is supplemented by DFT calculations.

13.
Chemistry ; 22(22): 7376-80, 2016 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-26994732

RESUMO

The reaction of stibinidene and bismuthinidene ArM [where Ar=C6 H3 -2,6-(CH=NtBu)2 ; M=Sb (1), Bi (2)] with transition metal (TM) carbonyls Co2 (CO)8 and Mn2 (CO)10 produced unprecedented ionic complexes [(ArM)2 Co(CO)3 ](+) [Co(CO)4 ](-) and [(ArM)2 Mn(CO)4 ](+) [Mn(CO)5 ](-) [where M=Sb (3, 5), Bi (4, 6)]. The pnictinidenes 1 and 2 behaved as two-electron donors in this set of compounds. Besides the M→TM bonds, the topological analysis also revealed a number of secondary interactions contributing to the stabilization of cationic parts of titled complexes.

14.
Chemistry ; 22(52): 18817-18823, 2016 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-27740701

RESUMO

Our studies have been focused on the synthesis of N→Ga coordinated organogallium sulfides [L1 Ga(µ-S)]3 (1) and [L2 Ga(µ-S)]2 (2) containing either N,C,N- or C,N-chelating ligands L1 or L2 (L1 is {2,6-(Me2 NCH2 )2 C6 H3 }- and L2 is {2-(Et2 NCH2 )-4,6-tBu2 -C6 H2 }- ). As the result of the different ligands, compounds 1 and 2 differ mutually in their structure. To change the Ga/S ratio, unusually N→Ga coordinated organogallium tetrasulfide L1 Ga(κ2 -S4 ) (3) was prepared and the unprecedented complex [{2-[CH{(CH2 )3 CH3 }(µ-OH)]-6-CH2 NMe2 }C6 H3 ]GaS (4) was also isolated as the minor by-product of the reaction. Compounds 1-3 were further studied as potential single-source precursors for amorphous GaS thin film deposition by spin-coating.

15.
Chemistry ; 22(16): 5620-8, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-26934563

RESUMO

Our attempts to synthesise N→M intramolecularly coordinated diorganometallic hydrides L2MH2 [M=Si (4), Ge (5), Sn (6)] containing the CH=N imine group (in which L is C,N-chelating ligand {2-[(2,6-iPr2C6H3)N=CH]C6 H4}(-)) yielded 1,1'-bis(2,6-diisopropylphenyl)-2,2'-spriobi[benzo[c][1,2]azasilole] (7), 1,1'-bis(2,6-diisopropylphenyl)-2,2'-spriobi[benzo[c][1,2]azagermole] (8) and C,N-chelated homoleptic stannylene L2Sn (10), respectively. Compounds 7 and 8 are an outcome of a spontaneous double hydrometallation of the two CH=N imine moieties induced by N→M intramolecular coordination (M=Si, Ge) in the absence of any catalyst. In contrast, the diorganotin hydride L2SnH2 (6) is redox-unstable and the reduction of the tin centre with the elimination of H2 provided the C,N-chelated homoleptic stannylene L2Sn (10). Compounds 7 and 8 were characterised by NMR spectroscopy and X-ray diffraction analysis. Because the proposed N→M intramolecularly coordinated diorganometallic hydrides L2MH2 [M=Si (4), Ge (5), Sn (6)] revealed two different types of reduction reactions, DFT calculations were performed to gain an insight into the structures and bonding of the non-isolable diorganometallic hydrides as well as the products of their subsequent reactions. Furthermore, the thermodynamic profiles of the different reaction pathways with respect to the central metal atom were also investigated.

16.
Chemistry ; 22(43): 15340-15349, 2016 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-27619080

RESUMO

A set of (3,3')-bis(1-Ph-2-R-1H-2,1-benzazaborole) compounds, in which R=tBu (Bab-tBu)2 , R=Dipp (Bab-Dipp)2 or R=tBu and Dipp (Bab-Dipp)(Bab-tBu), was synthesized and fully characterized using 1 H, 11 B, 13 C, and 15 N NMR spectroscopy as well as single-crystal X-ray diffraction analysis. The central HC(sp3 )-C(sp3 )H bond with restricted rotation at the junction of both 1H-2,1-benzazaborole rings displayed an intriguing reactivity. It was demonstrated that this bond is easily mesolytically cleaved using alkali metals to form the respective aromatic 1Ph-2R-1H-2,1-benzazaborolyl anions M+ (THF)n (Bab-tBu)- (M=Li, Na, K) and K+ (THF)n (Bab-Dipp)- . Furthermore, the central HC(sp3 )-C(sp3 )H bond of bis(1H-2,1-benzazaborole)s is also homolytically cleaved either by heating or photochemical means, giving corresponding 1Ph-2R-1H-2,1-benzazaborolyl radicals (Bab-tBu). and (Bab-Dipp). , which rapidly self-terminate. Nevertheless, their formation was unambiguously established by NMR analysis of the reaction mixtures containing products of the self-termination of the radicals after heating or irradiation. (Bab-Dipp). radical was also characterized using EPR spectroscopy. Importantly, it turned out that the essentially non-polarized HC(sp3 )-C(sp3 )H bond in (Bab-tBu)2 is also cleaved heterolytically with 2 equiv of MeLi, giving the mixture of Li+ (SOL)n (Bab-tBu)- (SOL=THF or Et2 O) and lithium methyl-substituted borate complex Li+ (SOL)n (Bab-tBu-Me)- in a diastereoselective fashion.

17.
Inorg Chem ; 55(4): 1587-94, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26828856

RESUMO

We report here the synthesis of new N→Sn-coordinated stannaoxidoborates H[LSnB4O6R4] {L = [2,6-(Me2NCH2)C6H3](-) and R = Ph (6), 4-Br-Ph (7), 3,5-(CF3)2-Ph (8), and 4-CHO-Ph (9)} containing a nonsymmetric SnB4O6 unit. Compounds 6-9 represent new derivatives of the pentaborates [B5O6R4](-) in which the central boron is substituted by a tin atom. Compounds 6-9 were characterized by means of elemental analysis, electrospray ionization mass spectrometry, and NMR spectroscopy and in the case of 6-8 also by single-crystal X-ray diffraction analysis. The structures of N→Sn-coordinated stannaoxidoborates 6-8 consist of a spirobicyclic arrangement, with two six-membered SnB2O3 rings at the tin atom providing the new stannaoxidoborate [LSnB4O6R4](-) motif, which is compensated for by the proton atom coordinated to the Me2N group of the ligand L. The linear and thermal properties of 6-9 were studied with the help of electronic absorption spectra and differential scanning calorimetry. In addition, the presence of the nonsymmetric stannaoxidoborate SnB4O6 unit in 6, 7, and 9 prompted us to investigate their second-order nonlinear-optical properties.

18.
Chemistry ; 21(21): 7820-9, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25877759

RESUMO

We report here the synthesis of new C,N-chelated chlorostannylenes and germylenes L(3) MCl (M=Sn(1), Ge (2)) and L(4) MCl (M=Sn(3), Ge (4)) containing sterically demanding C,N-chelating ligands L(3, 4) (L(3) =[2,4-di-tBu-6-(Et2 NCH2 )C6 H2 ](-) ; L(4) =[2,4-di-tBu-6-{(C6 H3 -2',6'-iPr2 )N=CH}C6 H2 ](-) ). Reductions of 1-4 yielded three-coordinate C,N-chelated distannynes and digermynes [L(3, 4) M]2 for the first time (5: L(3) , M=Sn, 6: L(3) , M=Ge, 7: L(4) , M=Sn, 8: L(4) , M=Ge). For comparison, the four-coordinate distannyne [L(5) Sn]2 (10) stabilized by N,C,N-chelate L(5) (L(5) =[2,6-{(C6 H3 -2',6'-Me2 )NCH}2 C6 H3 ](-) ) was prepared by the reduction of chlorostannylene L(5) SnCl (9). Hence, we highlight the role of donor-driven stabilization of tetrynes. Compounds 1-10 were characterized by means of elemental analysis, NMR spectroscopy, and in the case of 1, 2, 5-7, and 10, also by single-crystal X-ray diffraction analysis. The bonding situation in either three- or four-coordinate distannynes 5, 7, and 10 was evaluated by DFT calculations. DFT calculations were also used to compare the nature of the metal-metal bond in three-coordinate C,N-chelating distannyne [L(3) Sn]2 (5) and related digermyme [L(3) Ge]2 (6).

19.
Chemistry ; 21(47): 16917-28, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26434943

RESUMO

The reduction of N,C,N-chelated bismuth chlorides [C6H3-2,6-(CH=NR)2]BiCl2 [where R = tBu (1), 2',6'-Me2C6H3 (2), or 4'-Me2NC6H4 (3)] or N,C-chelated analogues [C6H2-2-(CH=N-2',6'-iPr2C6H3)-4,6-(tBu)2]BiCl2 (4) and [C6H2-2-(CH2NEt2)-4,6-(tBu)2]BiCl2 (5) is reported. Reduction of compounds 1-3 gave monomeric N,C,N-chelated bismuthinidenes [C6H3-2,6-(CH=NR)2]Bi [where R = tBu (6), 2',6'-Me2C6H3 (7) or 4'-Me2NC6H4 (8)]. Similarly, the reduction of 4 led to the isolation of the compound [C6H2-2-(CH=N-2',6'-iPr2C6H3)-4,6-(tBu)2]Bi (9) as an unprecedented two-coordinated bismuthinidene that has been structurally characterized. In contrast, the dibismuthene {[C6H2-2-(CH2NEt2)-4,6-(tBu)2]Bi}2 (10) was obtained by the reduction of 5. Compounds 6-10 were characterized by using (1)H and (13)C NMR spectroscopy and their structures, except for 7, were determined with the help of single-crystal X-ray diffraction analysis. It is clear that the structure of the reduced products (bismuthinidene versus dibismuthene) is ligand-dependent and particularly influenced by the strength of the N→Bi intramolecular interaction(s). Therefore, a theoretical survey describing the bonding situation in the studied compounds and related bismuth(I) systems is included. Importantly, we found that the C3NBi chelating ring in the two-coordinated bismuthinidene 9 exhibits significant aromatic character by delocalization of the bismuth lone pair.

20.
Inorg Chem ; 54(14): 6792-800, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-26114305

RESUMO

The syntheses of the compounds [L(1)SnCl][M(CO)5(SnCl3)] (3, M = W; 4, M = Cr), [L(1)SnCl]OTf (5), [L(1)SnCl][W(CO)5(SnCl2OTf)] (6), [L(1)SnOTf][OTf] (7), and [L(2)Sn(OTf)2] (8) with L(1) = {2,6-[(CH3)C═N(C6H3-2,6-(i)Pr2)2]C5H3N} (DIMPY) and L(2) = {2-[(CH3)C═N(C6H3-2,6-(i)Pr2)]-6-(CH3O)}C5H3N) is reported. The compounds were characterized by elemental analyses, (1)H, (13)C, (19)F, and (119)Sn NMR spectroscopy, electrospray ionization mass spectrometry, and single-crystal X-ray diffraction analyses (3·1.5C7H8, 5·CH2Cl2, 7·C7H8, 8). For compounds 7 and 8, the experimental work is accompanied by density functional theory calculations.

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