[(n-C_4H_9)_2Sn(2-PyCO_2)_2(H_2O)]的合成、晶体结构

利用三丁基氯化锡和2-吡啶甲酸在三乙胺存在下以1:1摩尔比反应,合成了非预期有机锡配合物[(n-C_4H_9)_2Sn(2-PyCO_2)_2(H_2O)].通过元素分析、红外光谱、核磁共振氢谱和X-射线单晶衍射对其结构进行了表征.测试结果表明,该配合物为单体结构,锡原子呈七配位畸变五角双锥构型.通过配位水分子和游离羰基氧原子的氢键作用,形成了二维网状结构.

Synthesis,Characterization and Crystal Structure of the Dimeric Organotin Compound:{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2)

The title compound,{[n-Bu_(2)Sn(O_(2)CCH_(2)CS_(2)NC_(4)H_(8))]_(2)O}_(2),has been synthesized by the reaction of(tetrahydro-pyrrodithiolocarbamoylthio)acetic acid with the di-n-bubyltin oxide in1∶1molar ratio.The complex has been characterized by elemental analysis,IR and NMR.The crystal structure of it has been determined by X-ray single crystal diffraction.And the results showed that the crystal belongs to triclinic system with space group P1and some crystal parameters:a=1.2202(9)nm,b=1.3158(10)nm,c=1.3804(10)nm,α=111.215(9)°,β=99.357(9)°,γ=96.075(10)°,V=2.006(2)nm 3,Z=1,F(000)=908,μ=1.489mm^(-1),D c=1.474g·cm^(-3),R_(1)=0.0375,wR_(2)=0.0839.The complex has a centrosymmetric dimer structure mode with a four-membered central endo-cyclic Sn_(2)O_(2)unit in which two bridged oxygen atoms both connect with an exo-cyclic tin atom which has a distorted octahedron.Each of the endo-cyclic tin atoms exhibits a distorted trigonal bipyramid coordination geometry with an additional weak coordination carboxylate oxygen.Four carboxylate ligands are divided into two types.And two of them are bidentate and connecting to each of exo-cyclic tin atoms by using both oxygen atoms,whereas the others bridge to each pair of exo-and endo-cyclic tin atoms utilizing one oxygen atom only.CCDC:220513.

N-Radical enabled cyclization of 1,n-enynes

Compared to the widely used carbon-centered radicals,N-radicals have been relatively unexplored owing to the lack of practical and convenient production methods.Over the past few years,benefitting from the resurgence of reliable and controllable radical chemistry,N-radicals have been produced via thermal decomposition,oxidants,metal salts,or electrocatalysis.Therefore,numerous N-radical enabled cyclization of 1,n-enynes methods have been developed,providing a versatile and concise synthetic platform for the preparation of complex cyclic systems and natural products containing elaborate ring frameworks.In this review,we will summarize recent advances in the promising field of radical chemistry focusing on the production methods of N-radicals and their cyclization patterns,associated mechanisms,unmet challenges,and future opportunities.

One-dimensional Chain Crown Ether Complexes Synthesis and Crystal Structure of ([K(DB18-crown-6)]_(2)(CH_(3)CN))[Pt(SCN)_(4)]

The complexe{[K(DB18-crown-6)]_(2)(CH_(3)CN)}[Pt(SCN)_(4)]was synthesized and characterized by elemental analysis,IR spectrum and X-ray diffraction analysis.The complexe belongs to monoclinic,space group c2/c with cell dimensions,a=2.5904(8),6=1.3653(4),c-1.84706(6)nm,β=123.811(4)°,V=5-339(3)nm^(3),Z=4,.Dcalcd=l.577 g/cm^(3),F(000)=2552,R_(1)=0.051 l,wR_(2)=0.1411.The complexe shows one-dimensional chain of{[K(DB18-crown-6)]+complex cation and[Pt(SCN),i]2-complex anion bridged by N atom of CHaCN moleculer between two[K(DB18-crown-6)]_(2)[Pt(SCN)_(4)]groups respectively.

Crystal Structure of A Novel Ionic Organotin Complex:{[Ph_(2)Sn]_(2)[2,6-(O_(2)C)_(2)C_(5)H_(3)N]_(3)H_(2)O}^(2-)[HNEt_(3)]_(2)^(+)

A novel ionic organotin complex{[Ph_(2)Sn]_(2)[2,6-(O_(2)C)_(2)]C_(5)H_(3)N}_(3)H_(2)O}^(2-)[HNEt_(3)]^(2+)has been unexpectedly obtained by the reaction of Ph_(3)SnCl and 2,6-pyridine dicarboxylic acid in 1:1 molar ratio in the presence of organic base Et_(3)N.Possible dephenylation mechanism was illustrated.The X-ray diffraction study has shown that the title complex consists of cation moiety[HNEt_(3)]^(+)and anion moiety{[Ph_(2)Sn]_(2)[2,6-(O_(2)C_(2))C_(5)H_(3)N]_(3)H_(2)O}^(2-)with tin(IV)in a pengonal bipyramidal coordination geometry.

The First Three-dimensional Crown Ether Complex:{[Na(B18-C-6)]_(6)[Pt(SCN)_(6)]}[Pt(SCN)_(6)](SCN)_(2)with Covalent Bond

The novel benzo-18-crown-6(B18-C-6)complex;{[Na(Bl8-C-6)]_(6)[Pt(SCN)_(6)]}[Pt(SCN)_(6)](SCN)_(2)(1)was synthesized and characterized by elemental analysis,IR spectrum and x-ray diffraction analysis.Thr crystal structure belongs to rhomobohedral,space group R-3 with cell dimesions:a=6=1.9933(3),c=2.9760(6)nm,α=β=90,γ=120°,V=10.240(3)nm^(3),Z=3,A,aclcd=1.564 g/cm^(3),F(000)=4908.1 is composed of one{[Na(B18-C-6)]_(6)[Pt(SCN)_(6)]}4+complex cation,one[Pt(SCN)_(6)]^(2-)complex anion and two SCN~anions.{[Na(B18-C-6)]_(6)[Pt(SCN)_(6)3}4+complex cation shows a three-dimensional network structure bridged by Na-O interactions between adjacent[Na(B18-C-6)]+units.The function of[Pt(SCN)_(6)]^(2-)complex anion and two SCN'anions are balancing charge in crystal.

α-、β-环糊精和十二烷基三甲基溴化铵主-客体包合作用的微量热研究

在 2 98 .15 K下 ,用微量热法测定了 α-、β-环糊精与表面活性剂十二烷基三甲基溴化铵在水溶液中包合作用的热效应。从 α-、β-环糊精的微观结构出发讨论了主 -客体的结合模式以及热力学数据的差异。