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Introduction: Over the past few years, we have seen some signs of change in mental health among cardiovascular surgeons. Suicide cases, troubled professional relationships, separations, and treatment of depression and anxiety are common occurrences in this group of surgeons. With this in mind, we decided to perform an analysis of the mental health of Brazilian cardiovascular surgeons., Methods: This is a cross-sectional qualitative study. Thirty-seven validated questionnaires (from the Diagnostic and Statistical Manual of Mental Disorders, fifth edition) were collected at the 46th Congress of the Sociedade Brasileira de Cirurgia Cardiovascular, in April 2019. It was authorized by the Faculdade da Saúde e Ecologia Humana Ethics Committee (CAAE-09479519.7.0000.5101). The questionnaires were analyzed by a psychiatrist who grouped the individuals with signs suggestive of some mental disorder., Results: The questions that pointed out signs and symptoms of possible anxiety, depression, alcohol or drug abuse, and burnout were selected in the questionnaire. Seventeen individuals (45.95%) did not score for any disorder. Twenty individuals (54.05%) in our sample had one or more disorders, with 43.24% (16 individuals) showing signs or symptoms compatible with anxiety - the World Health Organization data for Brazil show a 9.3% incidence of anxiety in the general population. We found signs of depression in 21.62% of our sample (5.8% in the general population), of alcohol or drug abuse in 27.03% (19.4% in the general population), and of burnout in 40.54% (32% in the general population)., Conclusion: Mental disorders are present in most cardiovascular surgeons studied.

Many organic and main-group compounds, usually acids or bases, can accelerate chemical reactions when used in substoichiometric quantities, a process known as organocatalysis. In marked contrast, very few of these compounds are able to activate carbon monoxide, and until now, none of them could catalyze its chemical transformation, a classical task for transition metals. Herein we report that a stable singlet ambiphilic carbene activates CO and catalytically promotes the carbonylation of an o -quinone into a cyclic carbonate. These findings pave the way for the discovery of metal-free catalyzed carbonylation reactions.

The first examples of Co(ii) mesoionic carbene complexes (CoX2DippMIC2; X = Cl-, Br-, I-) demonstrate a new electronic perturbation on tetrahedral Co(ii) complexes. Using absorption spectroscopy and magnetometry, the consequences of the MIC's strong σ-donating/minimal π-accepting nature are analyzed and shown to be further tunable by the nature of the coordinated halide.

It has been previously demonstrated that stable singlet electrophilic carbenes can behave as metal surrogates in the activation of strong E-H bonds (E = H, B, N, Si, P), but it was believed that these activations only proceed through an irreversible activation barrier. Herein we show that, as is the case with transition metals, the steric environment can be used to promote reductive elimination at carbon centers.

The coordination of Ge 9 Zintl clusters at (carbene)Cu I moieties is explored, and the complexes [(CAAC)Cu] 2 [η 3 -Ge 9 {Si(TMS) 3 } 2 ] (1), (CAAC)Cu[η 3 -Ge 9 {Si(TMS) 3 } 3 ] (2), and (MIC)Cu[η 3 -Ge 9 {Si(TMS) 3 } 3 ] (3) are compared with their known N-heterocyclic carbene (NHC) derivatives (A and B), where CAAC = cyclic (alkyl)amino carbene, MIC = mesoionic carbene, and TMS = trimethylsilane. In analogy to the NHC derivatives, the synthesis of 1-3 proceeds by single-step reactions of (CAAC)CuCl or (MIC)CuCl with the [Ge 9 R 2 ] 2- and [Ge 9 R 3 ] - [R = Si(TMS) 3 ] cluster ligands, respectively, and yields complexes of (carbene)Cu I (carbene = CAAC, MIC) moieties exhibiting η 3 -coordination modes of the Ge 9 deltahedron to the Cu atom. In 1, [Ge 9 R 2 ] 2- acts as a η 3 -bridging unit for two (CAAC)Cu I moieties, and 2 and 3 feature single (carbene)Cu I (CAAC and MIC) fragments η 3 -connected to [Ge 9 R 3 ] - units. Analysis of the bond lengths in comparison with known examples shows a bond expansion within the coordinated Ge 3 triangular faces for all (carbene)Cu I Ge 9 complexes (carbene = NHC, MIC, CAAC). All compounds are characterized by single-crystal X-ray diffractometry, NMR spectroscopy [ 1 H, 13 C{ 1 H}, and 29 Si{ 1 H}], electrospray ionization mass spectometry, elemental analysis (C, H, and N), and for the first time also by IR and Raman investigations (for 2 and 3). The new complexes add to the known NHC derivatives and extend the exploration of Ge 9 clusters with carbene ligands at Cu I atoms.

Cyclic (alkyl)(amino)carbenes with a six-membered backbone were prepared. Compared to their five-membered analogues, they feature increased % V bur and enhanced donor and acceptor properties, as evidenced by the observed n → π* transition trailing into the visible region. The high ambiphilic character even allows for the intramolecular insertion of the carbene into an unactivated C(sp 3 )-H bond. When used as ligands, they outcompete the five-membered analogues in the palladium-mediated α-arylation of ketones with aryl chlorides.

A novel synthetic route gives access to mesoionic carbene and cyclopropenylidene supported gold chloride complexes. The corresponding cationic MIC-gold complex obtained by chloride abstraction allows for the first transition metal-catalyzed functionalization of both nitrogens of parent hydrazine., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The copper-catalyzed 1,3-dipolar cycloaddition of an azide to a terminal alkyne (CuAAC) is one of the most popular chemical transformations, with applications ranging from material to life sciences. However, despite many mechanistic studies, direct observation of key components of the catalytic cycle is still missing. Initially, mononuclear species were thought to be the active catalysts, but later on, dinuclear complexes came to the front. We report the isolation of both a previously postulated π,σ-bis(copper) acetylide and a hitherto never-mentioned bis(metallated) triazole complex. We also demonstrate that although mono- and bis-copper complexes promote the CuAAC reaction, the dinuclear species are involved in the kinetically favored pathway.

1(st) Generation Hoveyda-Grubbs olefin metathesis catalyst was purposely decomposed in the presence of ethylene yielding inorganic species that are inactive in the ring-closing metathesis (RCM) of benchmark substrate diethyldiallyl malonate (DEDAM). The decomposed catalyst was treated with 1-(3,5-diisopropoxyphenyl)-1-phenylprop-2-yn-1-ol (3) to generate an olefin metathesis active ruthenium indenylidene-ether complex in 43 % yield. This complex was also prepared independently by reacting RuCl(2)(p-cymene)(PCy(3)) with organic precursor 3. The activity of the isolated reactivated catalyst in the RCM of DEDAM is similar to that of the independently prepared complex.

The reactions between several derivatives of 1-(3,5-dimethoxyphenyl)-prop-2-yn-1-ol and different ruthenium starting materials [i.e., RuCl₂(PPh₃)₃ and RuCl₂(p-cymene)(L), where L is tricyclohexylphosphine di-t-butylmethylphosphine, dicyclohexylphenylphosphine, triisobutylphosphine, triisopropylphosphine, or tri-n-propylphosphine] are described. Several of these reactions allow for the easy, in-situ and atom-economic preparation of olefin metathesis catalysts. Organic precursor 1-(3,5-dimethoxyphenyl)-1-phenyl-prop-2-yn-1-ol led to the formation of active ruthenium indenylidene-ether complexes, while 1-(3,5-dimethoxyphenyl)-prop-2-yn-1-ol and 1-(3,5-dimethoxyphenyl)-1-methyl-prop-2-yn-1-ol did not. It was also found that a bulky and strong σ-donor phosphine ligand was required to impart good catalytic activity to the new ruthenium complexes.