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The use of bis(NHC) manganese(I) complexes 3 as catalysts for the hydrogenation of esters was investigated. For that purpose, a series of complexes has been synthesized via an improved two step procedure utilizing bis(NHC)‐BEt3 adducts. By applying complexes 3 with KHBEt3 as additive, various aromatic and aliphatic esters were hydrogenated successfully at mild temperatures and low catalyst loadings, highlighting the efficiency of the novel catalytic system. The versatility of the developed catalytic system was further demonstrated by the hydrogenation of other substrate classes like ketones, nitriles, N‐heteroarenes and alkenes. Mechanistic experiments and DFT calculations indicate an inner sphere mechanism with the loss of one CO ligand and reveal the role of BEt3 as cocatalyst. [ABSTRACT FROM AUTHOR]

Manganese‐catalyzed hydrogenation reactions have aroused widespread interest in recent years. Among the catalytic systems described, especially PNP‐ and NNP–Mn pincer catalysts have been reported for the hydrogenation of aldehydes, ketones, nitriles, aldimines and esters. Furthermore, NNP−Mn pincer compounds are efficient catalysts for the hydrogenolysis of less reactive amides, ureas, carbonates, and carbamates. Herein, the synthesis and application of specific imidazolylaminophosphine ligands and the corresponding Mn pincer complexes are described. These new catalysts have been characterized and studied by a combination of experimental and theoretical investigations, and their catalytic activities have been tested in several hydrogenation reactions with good to excellent performance. Especially, the reduction of N‐heterocycles can be performed under very mild conditions. [ABSTRACT FROM AUTHOR]

A novel one‐pot iridium‐catalyzed domino hydroxymethylation of olefins, which relies on using two different ligands at the same time, is reported. DFT computation reveals different activities for the individual hydroformylation and hydrogenation steps in the presence of mono‐ and bidentate ligands. Whereas bidentate ligands have higher hydrogenation activity, monodentate ligands show higher hydroformylation activity. Accordingly, a catalyst system is introduced that uses dual ligands in the whole domino process. Control experiments show that the overall selectivity is kinetically controlled. Both computation and experiment explain the function of the two optimized ligands during the domino process. [ABSTRACT FROM AUTHOR]

The synthesis of different metal pincer complexes coordinating to the chiral PNP ligand bis(2‐((2R,5R)‐2,5‐dimethyl‐phospholanoethyl))amine is described in detail. The characterized complexes with Mn, Fe, Re and Ru as metal centers showed good activities regarding the reduction of several prochiral ketones. Comparing these catalysts, the non‐noble metal complexes produced best selectivities not only for aromatic substrates, but also for different kinds of aliphatic ones leading to enantioselectivities up to 99% ee. Theoretical investigations elucidated the mechanism and rationalized the selectivity. [ABSTRACT FROM AUTHOR]

The chemoselective dehydrogenative silylation and hydrogenation of 1,3‐divinyldisiloxane by using HSiMe3 catalyzed by CpFe(CO)2Me (Cp = η5‐cyclopentadienyl) was explored by DFT computations. The active catalyst, CpFe(CO)SiMe3, was generated from a CO‐assisted pathway and HSiMe3‐initiated acetaldehyde reductive elimination. Starting from the active catalyst, the dehydrogenative silylation step of the first vinyl group was found to be the rate‐determining step, and the subsequent chemoselective hydrogenation step of the second vinyl group was discovered to be kinetically more favored. Within the reaction, the oxygen atom of 1,3‐divinyldisiloxane was not found to play a role in competitive coordination. The computed results rationalize the experimentally observed chemoselectivity. [ABSTRACT FROM AUTHOR]

Abstract: A selection of cobalt(I) and cobalt(II) pincer type complexes with different substitution patterns was tested in the catalytic reduction of carboxylic acid esters to alcohols. The cobalt pincer type complex 4 is suitable for the hydrogenation of aromatic as well as aliphatic and cyclic esters. Mechanistic investigation indicated a metal ligand cooperated reaction pathway. [ABSTRACT FROM AUTHOR]

A new chiral manganese PNP pincer complex is described. The asymmetric hydrogenation of several prochiral ketones with molecular hydrogen in the presence of this complex proceeds under mild conditions (30-40 °C, 4 h, 30 bar H2). Besides high catalytic activity for aromatic substrates, aliphatic ketones are hydrogenated with remarkable selectivity (e.r. up to 92:8). DFT calculations support an outer sphere hydrogenation mechanism as well as the experimentally determined stereochemistry. [ABSTRACT FROM AUTHOR]

The first manganese-catalyzed hydrogenation of esters to alcohols has been developed. The combination of Mn(CO)5Br with [HN(CH2CH2P(Et)2)2] leads to a mixture of cationic and neutral Mn PNP pincer complexes, which enable the reduction of various ester substrates, including aromatic and aliphatic esters as well as diesters and lactones. Notably, related pincer complexes with isopropyl or cyclohexyl substituents showed very low activity. [ABSTRACT FROM AUTHOR]

The mechanism of acetonitrile and methyl benzoate catalytic hydrogenation using pincer catalysts M(H)2(CO)[NH(C2H4P iPr2)2] ( 1M) and M(H)(CO)[N(C2H4P iPr2)2] ( 2M) (M = Fe, Ru, Os) has been computed at various levels of density functional theory. The computed equilibrium between 1Fe and 2Fe agrees perfectly with the experimental observations. On the basis of the activation barriers and reaction energies, the best catalysts for acetonitrile hydrogenation are 1Fe/2Fe and 1Ru/2Ru, and the best catalysts for methyl benzoate hydrogenation are 1Ru/2Ru. The best catalysts for the dehydrogenation of benzyl alcohol are 1Ru/2Ru. It is to note that the current polarizable continuum model is not sufficient in modeling the solvation effect in the energetic properties of these catalysts as well as their catalytic properties in hydrogenation reaction, as no equilibrium could be established between 1Fe and 2Fe. Comparison with other methods and procedures has been made. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Selective catalytic reductions of nitriles are presented using the commercially available Ru-Macho-BH complex. A variety of aliphatic, aromatic and (hetero)cyclic nitriles including industrially important adipodinitrile are hydrogenated to the corresponding primary amines. Modelling suggests the reaction follows an outer sphere hydrogenation mechanism. [ABSTRACT FROM AUTHOR]

The first selective iridium-catalyzed hydrogenations of esters are presented. By using a commercially available iridium pincer complex more than 20 different aromatic, aliphatic, and (hetero)cyclic esters are reduced to the corresponding alcohols in moderate to very good yields. An outer-sphere mechanism is proposed on the basis of our computational analysis. [ABSTRACT FROM AUTHOR]

We present the first base-free Fe-catalyzed ester reduction applying molecular hydrogen. Without any additives, a variety of carboxylic acid esters and lactones were hydrogenated with high efficiency. Computations reveal an outer-sphere mechanism involving simultaneous hydrogen transfer from the iron center and the ligand. This assumption is supported by NMR experiments. [ABSTRACT FROM AUTHOR]

A convenient and efficient catalyst system for the hydrogenation of aliphatic nitriles towards the corresponding primary amines in high to excellent yields is presented. In addition, aromatic nitriles are reduced smoothly, too. The use of low catalyst loadings and molecular hydrogen make this protocol an attractive methodology. [ABSTRACT FROM AUTHOR]

The synthesis of phosphine-imidazolyl ligands 1 and 2 in good yields is presented. In combination with [{Ru(benzene)Cl2}2], ligands 1 c and 1 e formed efficient catalyst systems for the selective hydrogenation of various carboxylic esters into their corresponding primary alcohols. Furthermore, the structures of four ruthenium complexes with ligands 1 b, 1 c, 1 d, and 1 e were determined by X-ray crystallography, which showed the formation of different coordination modes depending on the ligand structure. [ABSTRACT FROM AUTHOR]

Abstract: Adsorption of reaction intermediates appearing during CO hydrogenation at the sulfur covered MoS2(10−10) surfaces, Mo-termination with 42% S coverage and S-termination with 50% S coverage, are investigated systematically using periodic density functional theory methods. Computed vibrational frequencies of all intermediates are compared with observed data from infrared (IR) spectroscopy allowing a detailed interpretation and assignment of the different features in the experimental spectra. The pathway for CO hydrogenation on both terminations has been studied in detail where the most likely reaction path involves C1 type surface species in the sequence CO→CHO→CH2O→CH2OH→CH2 →CH3 →CH4 in agreement with the experiment. [Copyright &y& Elsevier]

UB3LYP computation including dispersion and toluene solvation has been carried to elucidate the mechanisms of alkene hydrogenation catalyzed by bis(imino)pyridine iron dinitrogen complex (iPrPDI)Fe(N2)2, which has low stability towards N2 dissociation. The coordinatively unsaturated complexes, (iPrPDI)Fe(N2) and (iPrPDI)Fe(1-C4H8), favor open-shell singlet ground states. On the basis of our computations, we propose a new mechanism of 1-butene coordination and hydrogenation after N2 dissociation. The hydrogenation of 1-butene undergoes a concerted open-shell singlet transition state involving H2 dissociation, C-H bond formation and C=C bond elongation, as well as the subsequent C-H reductive elimination. In the whole alkene hydrogenation, the H-H bond cleavage is the rate-determining step. Graphical abstract The alkene hydrogenation catalyzed by redox-active pyridine(diimine)-chelate iron complex follows the open-shell singlet state path [ABSTRACT FROM AUTHOR]

The cover page of the journal "Angewandte Chemie International Edition" is presented.

Abstract: The entire catalytic hydrodesulfurization (HDS) cycle of benzothiophene over Mo3S9 cluster has been investigated at the level of density functional theory. It is found that the hydrogenation and hydrogenolysis route with dihydrobenzothiophene (DHBT) as intermediate is more favored than the hydrogenolysis and hydrogenation route with styrene as intermediate. The stepwise hydrogenolysis of SB–C9 (C(aryl)–S) bond in DHBT leading to the formation of 2-phenylethanethiol is more favored than that of SB–C2 (C(alkyl)–S) bond with 2-ethylthiophenol as intermediate. The computed activation free energy and rate constant of benzothiophene hydrogenation to DHBT agree well with the available experimental data. The difference in HDS reactivity between benzothiophene and thiophene has been discussed. [Copyright &y& Elsevier]

[Display omitted] • Mechanisms of alkene hydrogenation catalyzed by cationic Ni(II)-PNP complexes are computed. • Non-bifunctional inner-sphere mechanism with two possible and competitive routes is proposed. • One route undergoes concerted H 2 σ-bond metathesis in Ni(II) oxidation state. • One route undergoes H 2 oxidative addition/reductive elimination involving unusual Ni(IV) oxidation state. • Strong correlations between electronic and steric effects Gibbs free energy barriers are found. The hydrogenation mechanisms of alkenes catalyzed by square-planar cationic Ni(II)-PNHP hydride complexes have been computed (M06L-GD3-SCRF). It is found that the reaction prefers a non-bifunctional inner-sphere mechanism, the Ni(II)/Ni(IV) cycle involving H 2 oxidative addition forming unusual Ni(IV) oxidation state and reductive elimination is accessible and has been proven to be superior or competitive with the widely accepted Ni(II) cycle undergoing concerted H 2 σ-bond metathesis in formal Ni(II) oxidation state. Systematic investigations into the electronic and geometric effects of phosphine ligand substituents uncover their significant influence on the Gibbs free energy barrier of elementary steps, leading to differences in catalytic activity. Analysis into these effects demonstrates a strong correlation between the apparent free energy barrier and frontier orbital energy, natural charge of Ni-center and buried volume ratio of the catalyst. These findings offer valuable insights for the design of future catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • CO 2 hydrogenation over inverse supported Zr 9 O 18 /Ni(1 1 1) nanocatalyst was computed. • Charge transfer from Ni(1 1 1) to supported Zr 9 O 18 nanoparticle has been found. • Supported Zr 9 O 18 nanoparticle has coordinatively unsaturated Zr sites at interface. • H 2 prefers dissociative adsorption on Ni(1 1 1) and CO 2 activation prefers interface Zr sites. • Surface HCOO is the most important intermediate and methanol is the selective product. To tune the activity and selectivity of CO 2 hydrogenation, inverse supported Zr 9 O 18 /Ni(1 1 1) catalysts are designed based on ab initio molecular dynamics simulation and density functional theory calculation under the consideration of the number of interfacial O and Zr atoms as well as the interaction between O and Zr atoms. For the most stable catalyst with coordinatively unsaturated interface Zr sites, charge transfer from surface to oxide has been found. The Ni(1 1 1) surface is pre-covered by H atoms and the interface Zr sites can activate CO 2 to a large extent, and their interaction results in the spontaneous formation of surface formate. Further hydrogenation of surface formate leads to the selective formation of methanol with an apparent Gibbs free energy barrier of 0.62 eV, lower than that of methane formation (1.09 eV). On the contrary to metallic nickel and supported nickel catalysts, the most favoured methanol formation route [HCOO → CHO → CH 2 O → CH 3 O → CH 3 OH] does not involve CO as intermediate, revealing the mediated interface effect. [ABSTRACT FROM AUTHOR]

• Another available source of C 1 species is by HCO → CH + O, apart from CO → C + O. • Thermo stability of CH 2 species is a dominant factor in the CH 4 formation. • Different mechanisms of C 1 + C 1 couplings are found on the Fe surfaces. • Exposition of the Fe facets could tune CH 4 selectivity. To tune CH 4 selectivity of Fe-based Fischer-Tropsch synthesis (FTS) in the initial stage is of prime scientific and industrial importance to further improve the catalyst performance. Herein, distribution of CH 4 selectivity on the metallic Fe nanoparticle is predicted by DFT calculations and micro-kinetics analysis about the competition between C 1 hydrogenations and C 1 + C 1 couplings on abundant Fe surfaces including Fe(1 0 0), Fe(1 1 0), Fe(1 1 1), Fe(2 1 1), and Fe(3 1 0). The results show that HCO mechanism (HCO → CH + O) is an available source of C 1 species apart from CO direct dissociation. These Fe surfaces exhibit high effective barriers for CH 4 formation, which is linearly correlated to the thermal stability of CH 2 species. However, carbon chain prolongation on the more stable surfaces greatly depends on the coupling of C and CH species. On the less stable Fe(1 1 1) surface, the CO + C coupling is the main route for chain prolongation. Utilizing the effective barrier difference between the CH 4 formation and the most feasible C 1 + C 1 coupling as a descriptor of CH 4 selectivity, it is quantified that CH 4 selectivity decreases in sequence of Fe(1 0 0) > Fe(2 1 1) > Fe(1 1 0) > Fe(3 1 0) > Fe(1 1 1). It is revealed that thermal stability of the CH 2 species and exposition of the Fe facets could play essential roles in tuning CH 4 selectivity. Trying to expand the area of Fe(2 1 1), Fe(3 1 0) and especially Fe(1 1 1) surfaces would greatly suppress CH 4 selectivity without a decrease of activity. This work provides new insights and design principles for the Fe-based FTS catalysts. [ABSTRACT FROM AUTHOR]

The structures and stability of the designed PNP pincer amido M(NO) 2 (PNP) and amino H M(NO) 2 (PN H P) complexes [M = V, Nb, and Ta, PNP = N(CH 2 CH 2 P(isopropyl) 2 ) 2 , PN H P = HN(CH 2 CH 2 P(isopropyl) 2 ) 2 ] and their hydrogenation mechanisms for phenyl-substituted unsaturated functional groups have been explored at the B3PW91 level of density functional theory. Under H 2 environment, these conjugated complexes can form equilibrium and fulfill the criteria of metal–ligand cooperated bifunctional hydrogenation catalysts. For the hydrogenation of Ph-C N, Ph-CH NH, Ph-CH NH-Ph, Ph-CH N CH 2 Ph, Ph-C CH, Ph-CH CH 2 , Ph-CHO, and Ph-CO CH 3 , the reaction prefers either a two-step or one-step mechanism for the hydridic M H and protonic N H transfer. These results clearly show that the V, Nb, and Ta complexes are promising catalysts for the hydrogenation reactions, and these provide experimental challenges. [ABSTRACT FROM AUTHOR]

The mechanisms of CO hydrogenation with the formation of C 1 surface species on the clean and K 2 O-doped χ-Fe 5 C 2 (111) surfaces with carbon vacancies have been comparatively elucidated. On both surfaces, CO direct dissociation (CO → C + O) is not favored. On the clean surface, the preferred H-assisted pathway is CO → HCO → CH 2 O → CH 3 O → CH 3 OH. On the K 2 O-doped surface, the preferred paths are HCO → CHOH → CH + OH and HCO → CH 2 O → CH 2 OH → CH 2 + OH due to the barrier decrease of the C O bond cleavage of COH, CHOH and CH 2 OH by K 2 O promotion. These results might explain the K 2 O promoted carburization process and the formation of long-chain hydrocarbons. [ABSTRACT FROM AUTHOR]

The effect of Cu promoter on CH 4 formation from CO hydrogenation on Fe(100) has been investigated using spin-polarized density functional theory computations on periodic slab models. Two pathways of CH 4 formation are considered: (a) direct dissociation of CO followed by successive C hydrogenation and (b) successive hydrogenation of CO followed by deoxygenation of CH x O (x = 1–3). On the clean and Cu doped surfaces, direct dissociation of CO followed by successive C hydrogenation is more favorable kinetically and the overall CH 4 formation is endothermic. Compared with the clean surface, the Cu doped surface can suppress CH 4 formation by raising the barrier from the co-adsorbed CO + 4H. Methanol formation is unfavorable on both surfaces kinetically and thermodynamically. Reversely, methanol decomposition is favorable. It is also noted that Cu doping lowers the adsorption ability of the Fe(100) surface and therefore the adsorption energies of all species on the potential energy surfaces. [ABSTRACT FROM AUTHOR]

This developed protocol for the efficient Ru-catalyzed reduction of nitriles allows the conversion of aliphatic, aromatic, and heteroaromatic into the corresponding amines. [ABSTRACT FROM AUTHOR]

On the basis of spin-polarized periodic density functional theory including the latest dispersion correction (PBE-D3), the mechanisms of H 2 , O 2 , H 2 O, CO 2 , CO, CH 4 and C 2 H x dissociative adsorption on the hexagonal Mo 2 C surface have been computed. In our study we used the metallic Mo 2 C(001) surface as well as the Mo 2 C(101) surface with Mo/C = 1/1 ratio. It is found that the dissociative adsorptions of these small molecules are exothermic and have low barriers; and the Mo 2 C(001) surface has much stronger dissociative adsorption than the Mo 2 C(101) surface. In contrast to the Mo 2 C(001) surface, OH + H and O + 2H can form equilibrium on Mo 2 C(101) surface. For C 2 H x dissociative adsorption on the Mo 2 C(001) surface, C H bond dissociation is kinetically much more favorable than the C C bond dissociation, and the optimum C 2 H 6 dissociation route follows the order of C 2 H 6 → CH 3 CH 2 + H → C 2 H 4 + 2H → CH 2 CH + 3H → C 2 H 2 + 4H → C 2 H + 5H→ C 2 + 6H. Due to the very strong dissociative adsorption energies, both surfaces can be oxidized easily by using H 2 O; and high oxygen coverage can be expected. The Mo 2 C(001) surface can uptake more surface O atoms than the Mo 2 C(101) surface. These surfaces can also be carburized by using CH 4 , albeit in less extent. On the surface with co-adsorbed CO 2 + 4H; CO 2 dissociation (CO 2 → CO + O → C + 2O) is more favorable than the hydrogenation of CO 2 (CO 2 + H → HCOO or COOH) and CO (CO + H → HCO or COH). It is noted that CO 2 hydrogenation towards CH 4 formation is unlikely on the Mo 2 C(001) surface, while the effective barrier of surface C hydrogenation on the Mo 2 C(101) surface can be reduced by 2O and 2OH pre-covered surfaces. [ABSTRACT FROM AUTHOR]

Hydrogenations constitute fundamental processes in organic chemistry and allow for atom-efficient and clean functional group transformations. In fact, the selective reduction of nitriles, ketones, and aldehydes with molecular hydrogen permits access to a green synthesis of valuable amines and alcohols. Despite more than a century of developments in homogeneous and heterogeneous catalysis, efforts toward the creation of new useful and broadly applicable catalyst systems are ongoing. Recently, Earth-abundant metals have attracted significant interest in this area. In the present study, we describe for the first time specific molecular-defined manganese complexes that allow for the hydrogenation of various polar functional groups. Under optimal conditions, we achieve good functional group tolerance, and industrially important substrates, e.g., for the flavor and fragrance industry, are selectively reduced. [ABSTRACT FROM AUTHOR]

A variety of esters is reduced for the first time selectively using an iridium pincer-type complex as catalyst. [ABSTRACT FROM AUTHOR]

Abstract: The mechanism of ethanol synthesis from methanol under synthesis gas utilizing non-stoichiometric Mo20S43 and Mo20S36 clusters as model catalysts has been computed on the basis of density functional theory. The first step is methanol hydrogenolysis to form surface CH3, and the second step is CO insertion into surface CH3 to form surface acyl (CH3CO). The third step is surface acyl hydrogenation to form ethanol. [ABSTRACT FROM AUTHOR]

Abstract: The direct and H-mediated dissociation of CO2 on Ni(211) were investigated at the level of density functional theory. Although formate (HCOO) formation via CO2 hydrogenation was widely reported for CO2 adsorption on metal surfaces, it is found that on Ni(211) HCOO dissociation into CHO and O is much difficult, while direct dissociation of adsorbed CO2 into CO and O is more favorable. It is also found that the degree of electron transfer from surface to adsorbed CO2 correlates with the elongation of C–O bond lengths and the reduction of the CO2 dissociation barrier. [Copyright &y& Elsevier]

Abstract: Density functional theory calculations have been carried out on the reaction of ketene hydrogenation on Fe5C2(001) for the understanding of the Fischer–Tropsch synthesis mechanism. The main reaction pathway of ethene formation is CsH2CO→CCsH2 →CHCsH2 →CH2CsH2, and ethane formation follows CsH2CO→CCsH2 →CCsH3 →CCsH3 →CHCsH3 →CH2CsH3 →CH3CsH3, while that of ethanol is CsH2CO→[CsH3CO and/or CsH2CHO]→CsH3CHO→CsH3CH2O→CsH3CH2OH. Detailed comparison shows clearly that ketene dissociation with the formation of hydrocarbons is more favorable than the stepwise hydrogenation with the formation of ethanol. The expected product should be hydrocarbons rather than ethanol, in agreement with the experimental observation. [Copyright &y& Elsevier]

Abstract: Density functional theory computations have been carried out on the adsorption of NO, NO2, pyridine and pyrrole on the α-Mo2C(0001) surface for understanding the hydrodenitrogenation processes. On the Mo-terminated surface, NO decomposes into surface N and O, and NO2 dissociates into surface O and NO without any barriers, while the most stable adsorption modes of pyridine and pyrrole have π-face coordination over the three-fold molybdenum hollow sites with strongly destroyed aromatic systems. On the C-terminated surface, adsorbed surface species have been found for NO and NO2, while destroyed ring systems are found for pyridine and pyrrole. It is found that adsorption on the Mo-terminated surface is much stronger than that on the C-terminated surface. [Copyright &y& Elsevier]

• Coverage-dependent CO hydrogenation was computed and compared. • At 0.25 reasonable coverage CO dissociation prefers H-assisted path leading to CH formation. • Apparent barrier of methanation is in close agreement with experimental value. • Ketene is the intermediate from CH 2 and CO coupling for the first C-C bond formation. • CH 3 C is the homologue of CH and starts the cycle for chain propagation. For the first time the full catalytic cycle of CO activation, methanation and first C-C bond formation on Fe(110) at high coverage [0.25 ML, p (2 × 2)] have been computed by density functional theory. Under thermodynamic equilibrium, H-assisted CHO formation and CHO dissociation into CH+O are preferred thermodynamically and kinetically. Then CH can be transformed into methane via successive hydrogenation; and the first C-C bond can be formed by CH 2 and CO coupling resulting in ketene (CH 2 CO), which can be hydrogenated to acetyl (CH 3 CO). The next C-O dissociation of CH 3 CO results in CH 3 C (higher homologue CH), and this starts C-C chain growth and catalytic cycle. Both methanation and chain growth have the same rate-determining step as CHO dissociation. The computed apparent barrier of methanation is much close to experimental value. These high coverage results clearly explain the experimentally observed formation of methane as well as high hydrocarbons of synthesis gas conversion on metallic Fe surface. The computed vibrational frequencies of the proposed surface intermediates agree with the experimental data. This high coverage strategy should be applicable to other heterogeneous catalytic reactions having coverage preferences. Image, graphical abstract [ABSTRACT FROM AUTHOR]

A recently published protocol for hydrogenation of esters to alcohols is improved by using a sterically less hindered iron pincer complex, that shows superior catalytic activity. [ABSTRACT FROM AUTHOR]

The process involves a base-free reduction in the presence of the novel iron complex AIPC without any additives. [ABSTRACT FROM AUTHOR]