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Herein we report a transition-metal- and acid-free protocol for the reductive amination of carbonyl compounds with DMF using a substoichiometric amount of NaH2PO2·H2O. The general trends and limitations of the method were explored.

Syngas (a mixture of H2 and CO) is a synergistic reducing agent working much better than its components independently. In particular it allows to aminate carbonyl compounds with unstable functional groups furnishing the potential fungicides.

A total synthesis of the vasicinone family of natural products from bulk chemicals was developed. Reductive condensation of o-nitrobenzaldehydes with amines utilizing iron pentacarbonyl as a reducing agent followed by subsequent oxidation leads to a great variety of polycyclic nitrogen-containing heterocycles under mild conditions. Enantiomerically pure vasicinone, rutaecarpine, isaindigotone, and luotonin were synthesized from readily available starting materials like hydroxyproline, nitrobenzaldehyde, pyrrolidine, and piperidine in two to four operational steps without chromatography. The antifungal activity of all products was tested.

Borrowing hydrogen or the hydrogen autotransfer amination is a powerful approach to create single C-N bonds starting from stable and readily available substrates: amines and alcohols. It is considered as one of the most atom-efficient and green methods to synthesize complex amines. Herein, we attempted to arrange the array of the existing data in a comprehensive and structured manner and determine correlations between the experimental conditions and catalysis outcome both within different groups of cata-lysts and between the defined groups using the machine analysis. For each type of N-nucleophiles (aromatic, aliphatic, and heteroar-omatic amines, amides) the most efficient working conditions were suggested including attributing the optimal base and temperature regime for each metal.

The η6-fluorene cyclopentadienyl complexes [(η5-C5R5)M(η6-fluorene)](SbF6)2 (1: M = Co, R = Me; 2a: M = Rh, R = H; 2b: M = Ir, R = H) were synthesized by the iodide abstraction from [(η5-C5R5)MI2]n...

A comparative study of various widely used methods of reductive amination is reported. Specifically, such reducing agents as H2, Pd/C, hydride reagents [NaBH4, NaBH3CN, NaBH(OAc)3], and CO/Rh2(OAc)4 system were considered. For understanding the selectivity and activity of the reducing agents reviewed herein, different classes of starting materials were tested, including aliphatic and aromatic amines, as well as aliphatic and aromatic aldehydes and ketones. Most important advantages and drawbacks of the methods, such as selectivity of the target amine formation and toxicity of the reducing agents were compared. Methods were also considered from the viewpoint of green chemistry.

A total synthesis of the vasicinone family of natural products from bulk chemicals was developed. Reductive condensation of

The digest is devoted to the most widespread reducing agents which are used for the reduction of tertiary and secondary phosphine oxides, phospholene oxides, phospholane oxides, phosphonates, phosphinates, α- and β-hydroxy and thiomethyl phosphine oxides, α-aminophosphine oxides. Stereoselectivity of reactions is described. Methods of stabilization of phosphines which are prone to re-oxidation by the formation of borane-adduct or metal complexes are considered.

The reaction of tetraethyl [1,3-phenylenedi(methylene)]bis(phosphonate) with formyl derivatives of benzocrown-ethers or formyl derivatives of o-dimethoxybenzene lead to high yield formation of the respectful bis(crown ether) containing 1,3-distyrylbenzenes or tetramethoxy-substituted 1,3-distyrenebenzenes. NMR spectra and quantum-chemical calculations showed the prevalence of unsymmetrical syn/anti,(syn,anti),syn/anti-conformations in 1,3-distyrylbenzenes. 1,3-Distyrylbenzenes absorb in shorter wavelength spectral region and have a weaker fluorescence than 1,4-distyrylbenzenes. The difficulty in the electrochemical reduction of 1,3-distyrylbenzenes comparing with 1,4-distyrylbenzenes is due to a less effective conjugation system in the metaderivatives.

An improved method for the synthesis of two symmetric biscrown-containing and one model tetramethoxy-substituted 1,4-distyrylbenzenes was suggested. The structures of compounds were established by 1H and 13C NMR spectroscopy and X-ray diffraction analysis. Spectrophotometric and fluorescent titration were used to determine spectral properties, stoichiometry, and stability of complexes of biscrown-containing 1,4-distyrylbenzenes with alkali and alkaline-earth metal cations. The stability of the complexes was found to depend on the metal cation size and charge, as well as on the size of the crown ether fragment. The electrochemical oxidation and reduction potentials of the biscrown-containing 1,4-distyrylbenzenes and the model compound in solution were determined and their basic differences from the corresponding characteristics of biscrown-containing stilbenes were identified.