57693-32-0Relevant articles and documents
Synthesis of chelating complexes through solid-state dehydrochlorination reactions via second-sphere-coordination interaction with metal chlorides: A combined experimental-molecular modeling study
Guan, Hong-Yu,Wang, Zhen,Famulari, Antonino,Wang, Xu,Guo, Fang,Marti-Rujas, Javier
, p. 7438 - 7445 (2014)
We have applied crystal engineering as a tool to study the solid-state transformation from molecular salts to coordination complexes via mechanochemical dehydrochlorination reactions. The -(CH2) n- (n = 2, 3) alkyl chains were introduced into the bibenzylamine moiety to form the two nitrogen bases N,N,N′,N′- tetrabenzylethylenediamine (L1) and N,N,N′,N′- tetrabenzylpropydiamine (L2), which were self-assembled with tetrachlorometalates to form a series of supramolecular salts through second-sphere coordination. Single crystals of salts [L1]2H +·[CuCl4]2-·solvent (1) and [L2]2H+·[XCl4] 2-·solvent (2-4; X = Cu, Hg, Zn) were obtained and their structures determined by single-crystal X-ray diffraction. The effect of different alkyl chains (two and three -CH2- units) on the solid-state reactivity showed that the chelating complexes resulting from the mechanochemical dehydrohalogenation reaction depend on the formation of quasi-chelating hydrogen-bonding salts. Quantum-mechanical calculations have been used to gain insight in this mechanochemical dehydrohalogenation reaction, demonstrating that not only is size matching between reactants is important but also conformational energies, intermolecular interactions, and the symmetry of frontier molecular orbitals play an important role.
Tuning the inclusion properties and solid-state reactivity of second sphere adducts using conformationally flexible bidentate ligands
Guo, Fang,Wang, Xu,Guan, Hong-Yu,Yu, Hai-Bin,Li, Lei,Chen, Shan-Shan,Famulari, Antonino,Martí-Rujas, Javier
, p. 2842 - 2852 (2015/06/16)
Second-sphere coordination refers to any intermolecular interaction with the ligands directly bound to the primary coordination sphere of a metal ion. In this article, we have successfully applied the second-sphere coordination approach in the construction of versatile host frameworks that can accommodate various guest molecules. We have used a family of bidentate flexible molecules as second-sphere ligands, and the tetrachlorometalate anion [MCl4]2- (where M = Cu, Co, Cd, Zn, and Hg) as the primary coordination sphere to synthesize new second sphere adducts. By introducing an alkyl spacer -(CH2)n- (n = 1, 2, 3, 4) to bibenzylamine (L0), the ligands L1, L2, L3, and L4 with higher degree of flexibility were synthesized. Different guest molecules such as alcohol, acetic acid, acrylic ester, or acetonitrile can be included in the host framework self-assembling diprotonated L1-L4 and [MCl4]2-, leading to a novel type of supramolecular assemblies: CH3CH2OH[L2]2H+·[CuCl4]2- (2), CH3OH[L3]2H+·[MCl4]2- (3), CH3COOH[L3]2H+·[CuCl4]2- (4), CH2CHCOOCH3'[L3]2H+·[MCl4]2- (5-7), CH3CN·H2O'[L4]2H+·[MCl4]2- (8-9), and CH3OH'[L4]2H+·[MCl4]2- (10). L2 forms the quasi-chelating charge-assisted N-H···Cl hydrogen bonds with [MCl4]2- that can transform in the solid-state to a chelated coordination complex following a mechanochemical dehydrochlorination reaction. By increasing the number of methylene groups, ligands L3 and L4 exhibit considerable conformational diversity due to the higher flexibility induced by the backbone chains. The -(CH2)n- spacer lengths of the ligands influences the structural dimensionality, and its solid-state mechanochemical reactivity preventing the transformation from salt [L3-4]2H+·[MCl4]2- to the chelating coordination complex [(MCl2)(L3-4)]. Moreover, the thermal stability of the second sphere adducts has been monitored by thermogravimetric analyses and X-ray powder diffraction (PXRD). We demonstrate that some of the second sphere adducts are dynamic, showing reversible guest release/uptake involving crystalline-to-amorphous-to-crystalline phase transformations. QuantumMechanical (QM) demonstrate that ligands with backbone lengths longer than -(CH2)2- are reticent to react via dehydrochlorination reaction because of the backbone chain length, the symmetry and orientation of the frontier molecular orbitals (FMOs), while for the -(CH2)2-, the length and orientation of the FMOs is optimal for the reaction to occur.
Sml2-mediated carbon-carbon bond fragmentation in a-aminomethyl malonates
Xu, Qiongfeng,Cheng, Bin,Ye, Xinshan,Zhai, Hongbin
supporting information; experimental part, p. 4136 - 4138 (2009/12/30)
A new and efficient samarium diiodide-promoted carbon-carbon bond fragmentation reaction of α-aminomethyl malonates, taking place normally at room temperature and generating the corresponding deaminomethylation products In 74-94% yields, is reported. The presence of the amino group Is necessary for the success of the current transformation.
Highly selective N-Alkylation of amines promoted on silica: An efficient and recyclable surface
Basu, Basudeb,Paul, Susmita,Nanda, Ashis K.
experimental part, p. 1115 - 1120 (2010/05/02)
N-Alkylation of amines suffers from competing over alkylations. At the same time, use of strong base and other harsh conditions greatly limits providing a practical, generalized and selective procedure. Activated silica gel has been found to promote N-alkylations of amines. Here, we studied N-alkylation of amines with various types of alkyl halides, which finally constitute practical, highly selective and eco-friendly conditions for mono- or bis-alkylated amines at ambient temperature with recyclability of silica.
Aqueous-mediated N-alkylation of amines
Singh, Chingakham B.,Kavala, Veerababurao,Samal, Akshaya K.,Patel, Bhisma K.
, p. 1369 - 1377 (2008/09/17)
Direct N-alkylation of primary amines to secondary/tertiary amines and of secondary amines to tertiary amines has been achieved in excellent yields by employing alkyl, benzylic and allylic halides in the presence of NaHCO 3 in an aqueous medium at an elevated temperature. Amines of different stereoelectronic nature react with ease with different halides. The selective formation of secondary amines and the formation of three different substituted tertiary amines are some of the interesting features of this methodology. Reaction in an aqueous medium, operationally convenient conditions, excellent yields and innocuous byproducts, and the absence of transition-metal catalysts, expensive bases, solid supports and the formation of undesired quaternary ammonium salts makes this method a green chemical process. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
Synthesis of Vicinal Diamines by SmI2-Promoted Reduction of N-(N',N'-Dialkylaminoalkyl)benzotriazoles
Aurrecoechea, Jose M.,Fernandez-Acebes, Alvaro
, p. 4763 - 4766 (2007/10/02)
N-(N',N'-Dialkylaminoalkyl)benzotriazoles, derived from aldehydes and secondary amines, react with one equivalent of samarium iodide (SmI2), under mild conditions, to afford tertiary vicinal diamines, as a result of C-C coupling between two dialkylaminoalkyl moieties.
A Novel Method for the Synthesis of Symmetrical Vicinal Tertiary and Secondary Diamines
Katritzky, Alan R.,Fan, Wei-Qiang,Fu, Cong
, p. 3209 - 3213 (2007/10/02)
A variety of symmetrical vicinal tertiary and secondary diamines are readily prepared in good to excellent yields by either Grignard reaction or reduction of the glyoxal bisproducts with benzotriazole and secondary or primary amines.
