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1.
Int J Clin Pract ; 75(2): e13786, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33103321

RESUMO

PURPOSE: In our study, we aimed to evaluate the sleep quality, insomnia presence and severity, obstructive sleep apnoea syndrome (OSAS) risk of the patients who applied to family health centres and to determine the situations that might be related with these features. METHODS: This study is a descriptive research and conducted in Ankara Güdül, Antalya Degirmenözü, Bursa Sirameseler, Gaziantep Family Health Centre policlinics. The study population consisted of all patients over 18 years of age who were admitted to the family health centres for any reason. A 10-question questionnaire, Berlin questionnaire, Pittsburgh sleep quality questionare and insomnia severity questionare were applied by the researchers from October to December 2017 by using face-to-face interview method. RESULTS: Two hundred nineteen nine people participated in study and 54.5% of them were women. According to the results of Pittsburgh Sleep Quality Questionare, it was found that 27.1% of the participants' sleep quality was good; according to the Berlin sleep questionnaire, 27.4% of the participants had high OSAS risk. According to Insomnia Severity Questionare, 27.1% of them had insomnia lower threshold, 15.4% had moderate insomnia and 3.7% severe insomnia. CONCLUSIONS: In this context, it will be very effective in terms of the quality of life of patients in order to determine the conditions that disrupt sleep hygiene and to perform the necessary interventions which can be intervened in the primary healthcare institutions and the other patients to be delivered to the related upper levels.


Assuntos
Apneia Obstrutiva do Sono , Distúrbios do Início e da Manutenção do Sono , Adolescente , Adulto , Feminino , Humanos , Masculino , Atenção Primária à Saúde , Qualidade de Vida , Sono , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia
2.
Chemistry ; 24(57): 15387-15391, 2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30095190

RESUMO

A new isomer of borepin, identified as 2-borabicyclo[3.2.0]hepta-3,6-diene by single-crystal X-ray diffraction and heteronuclear NMR spectroscopy, was obtained by reaction of 1-mesityl-2,3,4,5-tetraphenylborole with the diaminoalkyne bis(piperidyl)acetylene. Analogous reactions of the alkyne with other borole derivatives generated seven-membered borepins, in which a second equivalent of the alkyne was found to insert into the exocyclic B-C bond. Results of mechanistic DFT studies as well as differences in the reactivity of the boroles toward the diaminoalkyne are discussed.

3.
Chem Commun (Camb) ; 54(67): 9349-9351, 2018 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-30074595

RESUMO

Two unusual reactions were demonstrated with iminoboranes, both leading to aminoboranes of the type R2B[double bond, length as m-dash]NR2. In one case, a carboboration of di(tert-butyl)iminoborane with B(C6F5)3 led to (tBu)(C6F5)B-N(tBu)(B(C6F5)2). In the other, a transient IDipp (1,3-di(2,6-diisopropylphenyl)imidazol-2-ylidene) adduct of MesBNtBu undergoes a shift of one carbene-bound Dipp substituent to the iminoborane nitrogen atom, yielding (1-Dipp-imidazol-2-yl)(Mes)B-N(Dipp)(tBu). Mechanistic DFT studies indicate the intermediacy of a borane·iminoborane adduct in the carboboration reaction.

4.
Nat Commun ; 9(1): 1197, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29567960

RESUMO

Molecules containing multiple bonds between atoms-most often in the form of olefins-are ubiquitous in nature, commerce, and science, and as such have a huge impact on everyday life. Given their prominence, over the last few decades, frequent attempts have been made to perturb the structure and reactivity of multiply-bound species through bending and twisting. However, only modest success has been achieved in the quest to completely twist double bonds in order to homolytically cleave the associated π bond. Here, we present the isolation of double-bond-containing species based on boron, as well as their fully twisted diradical congeners, by the incorporation of attached groups with different electronic properties. The compounds comprise a structurally authenticated set of diamagnetic multiply-bound and diradical singly-bound congeners of the same class of compound.

5.
Angew Chem Int Ed Engl ; 56(45): 14287-14292, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-28892234

RESUMO

Under a CO atmosphere, the dihydrodiborene [(cAAC)HB=BH(cAAC)] underwent coordination of CO concomitant with reversible hydrogen migration from boron to the carbene carbon atom, as well as reversible CO insertion into the B=B bond. Heating the CO adduct resulted in two unusual cAAC ring-expansion products, one presenting a B=C bond to a six-membered 1,2-azaborinane-3-ylidene, the other an unprecedented nine-membered cyclic alkyne resulting from reductive cleavage of CO and spontaneous formation of a C≡C bond.

6.
Angew Chem Int Ed Engl ; 56(37): 11263-11267, 2017 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-28640395

RESUMO

Deprotonation of [(cAAC)BH2 (CN)] provided clean access to the stable boryl anion, [(cAAC)BH(CN)]- . Whereas the addition of soft electrophiles occurred at the nucleophilic boron center, harder silyl electrophiles added to the harder terminal cyano nitrogen. The resulting [(cAAC)BH(CNSiPh3 )] species behaved like a silylium boryl nucleophile as well as a neutral silylisonitrile borylene.

7.
Chemistry ; 23(33): 8006-8013, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28430374

RESUMO

Electronic and steric factors have been investigated in the thermal ring expansion of boroles with organic azides, a reaction that provides access to highly arylated 1,2-azaborinines, BN analogues of benzene. Reactions of a variety of boroles and organic azides demonstrate that the synthetic method is quite general in furnishing 1,2-azaborinines, but the respective reaction rates reveal a strong dependence on the substituents on the two reactants. The products have been characterized by UV/Vis, electrochemical, NMR, and X-ray diffraction methods, clarifying their constitutions and highlighting substituent effects on the electronic structure of the 1,2-azaborinines. Furthermore, analysis of several possible mechanistic pathways for 1,2-azaborinine formation, as studied by DFT, revealed that a two-step mechanism involving azide-borole adduct formation and nitrene insertion is favored.

8.
Chem Commun (Camb) ; 52(90): 13249-13252, 2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27774552

RESUMO

The reaction of the vicinal biscarbenoid Pip-C[triple bond, length as m-dash]C-Pip with dimethyltin dichloride yields a unique tetraamino-substituted cyclobutadienyl system featuring a dative C-Sn interaction. DFT investigation of the reaction mechanism revealed that coordination of the stannyl fragment to the nucleophilic carbon leads to a metal-stabilised zwitterion, allowing for [2+2] cycloaddition under thermal conditions. The compound features a homoaromatic π-system comprising the three sp2-hybridised carbon atoms of the four-membered ring as a consequence of charge separation.

9.
Angew Chem Int Ed Engl ; 55(46): 14464-14468, 2016 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-27730749

RESUMO

Reduction of carbene-borane adduct [(cAAC)BBr2 (CN)] (cAAC=1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethylpyrrolidin-2-ylidene) cleanly yielded the tetra(cyanoborylene) species [(cAAC)B(CN)]4 presenting a 12-membered (BCN)4 ring. The analysis of the Kohn-Sham molecular orbitals showed significant borylene character of the BI atoms. [(cAAC)B(CN)]4 was found to reduce two equivalents of AgCN per boron center to yield [(cAAC)B(CN)3 ] and fragmented into two-coordinate boron(I) units upon reaction with IMeMe (1,3,4,5-tetramethylimidazol-2-ylidene) to yield the corresponding tricoordinate mixed cAAC-NHC cyanoborylene. The analogous cAAC-phosphine cyanoborylene was obtained by reduction of [(cAAC)BBr2 (CN)] in the presence of excess phosphine.

10.
Chemistry ; 22(48): 17169-17172, 2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-27685839

RESUMO

Room temperature hydrogenation of an SIDep-stabilized diboryne (SIDep=1,3-bis(diethylphenyl)-4,5-dihydroimidazol-2-ylidene) and a cAAC-supported diboracumulene (cAAC=1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethylpyrrolidin-2-ylidene) provided the first selective route to the corresponding 1,2-dihydrodiborenes. DFT calculations showed an overall exothermic (ΔG=19.4 kcal mol-1 ) two-step asynchronous H2 addition mechanism proceeding via a bridging hydride.

11.
Chemistry ; 22(39): 13815-13818, 2016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27428270

RESUMO

The reactivity of the diaminoacetylene Pip-C≡C-Pip (Pip=piperidyl=NC5 H10 ) towards phenyldichloro- and triphenylborane is presented. In the case of the less Lewis acidic PhBCl2 , the first example of a double Lewis adduct of a vicinal dicarbenoid is reported. For the more Lewis acidic triphenylborane, coordination to the bifunctional carbene leads to a mild B-C bond activation, resulting in a syn-1,2-carboboration. Ensuing cis/trans isomerization yields a novel ethylene-bridged frustrated Lewis pair (FLP). The compounds were characterized using multinuclear NMR spectroscopy, structural analysis, and mass spectrometry. Reactivity studies of both isomers with the N-heterocyclic carbene 1,3-dimethylimidazol-2-ylidene (IMe) aided in elucidating the proposed isomerization pathway. DFT calculations were carried out to elucidate the reaction mechanism. The rather low free energy of activation is consistent with the observation that the reaction proceeds smoothly at room temperature.

12.
Angew Chem Int Ed Engl ; 55(37): 11271-5, 2016 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-27374193

RESUMO

Among the numerous routes organic chemists have developed to synthesize benzene derivatives and heteroaromatic compounds, transition-metal-catalyzed cycloaddition reactions are the most elegant. In contrast, cycloaddition reactions of heavier alkene and alkyne analogues, though limited in scope, proceed uncatalyzed. In this work we present the first spontaneous cycloaddition reactions of lighter alkene and alkyne analogues. Selective addition of unactivated alkynes to boron-boron multiple bonds under ambient conditions yielded diborocarbon equivalents of simple aromatic hydrocarbons, including the first neutral 6 π-aromatic diborabenzene compound, a 2 π-aromatic triplet biradical 1,3-diborete, and a phosphine-stabilized 2 π-homoaromatic 1,3-dihydro-1,3-diborete. DFT calculations suggest that all three compounds are aromatic and show frontier molecular orbitals matching those of the related aromatic hydrocarbons, C6 H6 and C4 H4 (2+) , and homoaromatic C4 H5 (+) .

13.
Chemistry ; 22(33): 11736-44, 2016 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-27388206

RESUMO

Boryl, borylene, and base-stabilized borylene complexes of manganese and iron undergo a range of different reactions when treated with isonitriles including single, double, and partial isonitrile insertions into metal-boron bonds, ring formation, isonitrile coupling, and the liberation of new monovalent boron species. Two of the resulting cyclic species have also been found to react selectively with anhydrous HCl to form ring-opened products. The diverse isonitrile-promoted reactivity of transition-metal-boron compounds has been explored computationally.

14.
Nat Chem ; 8(7): 638-42, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27334631

RESUMO

The metals of the s block of the periodic table are well known to be exceptional electron donors, and the vast majority of their molecular complexes therefore contain these metals in their fully oxidized form. Low-valent main-group compounds have recently become desirable synthetic targets owing to their interesting reactivities, sometimes on a par with those of transition-metal complexes. In this work, we used stabilizing cyclic (alkyl)(amino)carbene ligands to isolate and characterize the first neutral compounds that contain a zero-valent s-block metal, beryllium. These brightly coloured complexes display very short beryllium-carbon bond lengths and linear beryllium coordination geometries, indicative of strong multiple Be-C bonding. Structural, spectroscopic and theoretical results show that the complexes adopt a closed-shell singlet configuration with a Be(0) metal centre. The surprising stability of the molecule can be ascribed to an unusually strong three-centre two-electron π bond across the C-Be-C unit.

15.
Chemistry ; 22(25): 8596-602, 2016 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-27159272

RESUMO

Heating the metalloborylene complex [{(η(5) -C5 Me5 )Fe(CO)2 }(µ-B){Cr(CO)5 }] with alkynes and diynes leads to the formation of B-metallated borirenes and a bis(B-metallated borirene) through formal transfer of the metalloborylene moiety [(η(5) -C5 Me5 )(OC)2 Fe(B:)]. By using this protocol, a range of B-metallated borirenes with electron-donating and electron-withdrawing substituents are prepared, and these are studied spectroscopically, structurally, and computationally. The yellow-orange color of the complexes is additionally explained through time-dependent density functional theory calculations.

16.
Angew Chem Int Ed Engl ; 55(16): 5076-80, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-26990148

RESUMO

The complete scission of the carbon-oxygen bond of carbon monoxide, while frequently observed on bulk metals and with bimetallic and cluster transition metal complexes, is unknown with monometallic systems. Reaction of a zerovalent iron bis(borylene) complex with a cyclic (alkyl)(amino)carbene revealed a highly selective intramolecular cleavage of the C-O bond of a carbonyl ligand at room temperature, leading to the formation of a highly unusual iron complex containing a base-stabilized (bora)alkylideneborane ligand. DFT investigation of the reaction mechanism suggested that the two Lewis acidic borylene boron atoms cooperate to cleave the C-O multiple bond.

17.
Chem Commun (Camb) ; 51(88): 15917-20, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26360103

RESUMO

The first examples of cis-configured diborenes - and the first cyclic diborenes - are isolated by taking advantage of stabilisation by chelating diphosphine ligands. The diborenes are prepared by a convenient one-pot reductive procedure that circumvents the need for a pre-formed base-adduct of the boron-containing precursor.

18.
Chemistry ; 21(35): 12357-62, 2015 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-26241579

RESUMO

An improved synthetic route to homoleptic complex [Pt(CAAC(Me))2] (CAAC = cyclic (alkyl)(amino)carbenes) and convenient routes to new heteroleptic complexes of the form [Pt(CAAC(Me))(PR3)] are presented. Although the homoleptic complex was found to be inert to many reagents, oxidative addition and metal-only Lewis pair (MOLP) formation was observed from one of the heteroleptic complexes. The spectroscopic, structural, and electrochemical properties of the zero-valent complexes were explored in concert with density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. The homoleptic [Pt(CAAC)2] and heteroleptic [Pt(CAAC)(PR3)] complexes were found to be similar in their spectroscopic and structural properties, but their electrochemical behavior and reactivity differ greatly. The unusually strong color of the CAAC-containing Pt(0) complexes was investigated by TD-DFT calculations and attributed to excitations into the LUMOs of the complexes, which are predominantly composed of bonding π interactions between Pt and the CAAC carbon atoms.

19.
Chemistry ; 21(31): 11056-64, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26111216

RESUMO

Taking advantage of an improved synthesis of [Ti(η(6) -C6 H6 )2 ], we report here the first examples of ansa-bridged bis(benzene) titanium complexes. Deprotonation of [Ti(η(6) -C6 H6 )2 ] with nBuLi in the presence of N,N,N',N'',N''-pentamethyldiethylenetriamine (pmdta) leads to the corresponding 1,1'-dilithio salt [Ti(η(6) -C6 H5 Li)2 ]⋅pmdta that enables the preparation of the first one- and two-atom-bridged complexes by simple salt metathesis. The ansa complexes were fully characterized (NMR spectroscopy, UV/Vis spectroscopy, elemental analysis, and X-ray crystallography) and further studied electrochemically and computationally. Moreover, [Ti(η(6) -C6 H6 )2 ] is found to react with the Lewis base 1,3-dimethylimidazole-2-ylidene (IMe) to give the bent sandwich complex [Ti(η(6) -C6 H6 )2 (IMe)].

20.
Chemistry ; 21(26): 9339-42, 2015 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-26013999

RESUMO

The preparation of [3]thoro- and [3]uranocenophanes, the first structurally authenticated ansa-bridged complexes of actinocenes, is reported. Following a flytrap route, 1,2-bis(cyclooctatetraenyldimethylsilyl)methane was synthesized, reduced to its tetraanion, and subsequently converted into bridged uranocene and thorocene complexes by salt metathesis with the corresponding actinide tetrachlorides. In addition, their electronic structures have been investigated by experimental (UV/Vis spectroscopy, cyclic voltammetry) and theoretical (DFT) methods.

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