Ultrasonicwave-assisted tandem-reaction for synthesis of symmetrical vicinal diamines

A practical synthesis of symmetrical vicinal diamines with broad chemistry scope is described. The key step is the ultrasonicwave promoted tandem-reaction, two-step reaction sequence combining Mannich double condensations with benzo- triazole, glyoxal and primary or secondary amines and reduction of the bis（benzotriazole）-adducts with sodium borohydride proceeded smoothly in tetrahydrofuran in high yield at room temperature.

Asymmetric Synthesis of Fluorinated Vicinal Diamines from Fluoromethyl Sulfinyl Imines and Diphenylmethylene-Benzylamines

A novel strategy was developed for the asymmetric synthesis of fluorinated vicinal diamines.Deprotonation of N-(diphenylmethylene)-benzylamines under base,followed by asymmetric nucleophilic addition to N-tert-butanesulfinylfluoroacetaldimines,a pair of diastereomeric isomers were afforded.The diastereomeric isomers can be easily separated from each other by silica gel column chromatography.The absolute steric configuration of two isomers was confirmed by single crystal X-ray diffraction analyses.The proposed mechanism revealed that the configuration of the carbon next to tert-butanesulfinyl was well controlled to be R by the chiral auxiliary.

Synthesis and Cytotoxic Evaluation of Novel Platinum(Ⅱ) Complexes with C2-Asymmetric and C2-Symmetric Chiral Vicinal Diamines

A series of new platinum（II） complexes with C2-asymmetric and C2-symmetric 1,2-diamines were designed and synthesized by convenient methods, involving samarium diiodide induced reductive coupling as the key step. The results of cytotoxicity showed that compounds （R,R）-lla and （S,S）-lla, two novel platinum（II） complexes with asymmetric 1,2-diamines, exhibited more potent cytotoxicity than that of oxaliplatin against all leukemia cell lines. Interestingly, （R,R）-lla and （S,S）-lla demonstrated less potent activity against three solid cancer cell lines than that of oxaliplatin, which indicated that these two compounds may only selectively inhibit the leukemia cell lines. In contrast, （R,R）-ISa and （S,S）-15a, two platinum（II） complexes with symmetric 1,2-diamines, showed similar cyto- toxicity to that of oxaliplatin against all leukemia cell lines and more potent activity against solid cancer cell lines. Further flow cytometry data indicated that （R,R）-lla could obviously arrest leukemia K562 cells in G2/M phases.

Synthesis of 2,3-Diaminoindoles via a Copper-Iodine Co-catalytic Strategy

A one-pot synthesis of vicinal diamines using indoles,azoles and phenothiazines in a tandem multi-component reaction is developed.The utilization of a copper-iodine co-catalytic system enables the generation of a diverse range of vicinal diaminoindoles with good selectivity and moderate to good yields.An attractive aspect of this method is that it can be conducted under mild and environmentally friendly conditions,showcasing its potential as an alternative approach for synthesizing vicinal diamines.Moreover,the use of a multicomponent tandem reaction highlights the power and versatility of such strategies in synthetic chemistry.

Tri-n-butylphosphane catalyzed ring opening of aziridines with secondary amines

Ring opening of aziridine with dialkyl amine took place readily in the presence of catalytic amounts of tri-n-butylphosphane （10 mol%） in the mixture of CH3CN/H20 （10：1）, giving corresponding vicinal diamines in mediate to high yields （58-95%） with good regioselectivitie, while aromatic secondary amine could not react under the same conditions. Tri-n-butylphosphane exhibited different catalytic selectivity to amines from Lewis acid catalysts.