Polystyrene-supported organotin dichloride as a recyclable catalyst in lactone ring-opening polymerization: assessment and catalysis monitoring by high-resolution magic-angle-spinning NMR spectroscopy

Dialkyltin dichloride grafted to a cross-linked polystyrene, with the formula [P-H]((1-t))[P-(CH2)nSnBuCl2]t (P=[CH2CH(pC6H4)], t=the degree of functionalization, and n=6 or 11), is investigated as a recyclable catalyst in the ring-opening polymerization (ROP) of epsilon-caprolactone (CL). It is demonstrated that high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy is an invaluable tool to characterize completely the supported catalyst. The 2D 1H-13C HSQC HR-MAS spectrum, in particular, allowed extensive assignment of the 1H and 13C resonances, as well as accurate measurement of the (n)J((1)H-(117/119)Sn) and (n)J((13)C-(117/119)Sn) coupling constants. 1H and 119Sn HR-MAS NMR spectroscopy is presented as a monitoring tool for catalytic processes based on organotin compounds, particularly for the investigation of the extent to which polymerization residues are observable in situ in the material pores and for the assessment of the chemical integrity and recycling conditions of the grafted catalyst. From polymerization experiments with CL, initiated by n-propanol and with [P-H]((1-t))[P-(CH2)nSnBuCl2]t of various compositions as the supported catalyst, it appears that a partial 'burst' of the polystyrene support occurs when the length of the alkyl spacer is limited to n=6, as a result of polymer chains growing within the pores of the support. However, extension of the length of the aliphatic polymethylene spacer from 6 to 11 carbon atoms preserves the support integrity and allows the production of catalyst-deprived poly(epsilon-caprolactone) (PCL) oligomers. A preliminary attempt to recycle the heterogeneous catalyst has shown that very good reproducibility can be obtained, in terms of both catalyst activity and molecular-weight parameters of the as-recovered PCL polyester chains.     

Synthesis and Characterization of Biologically Potent Di‐organotin(IV) Complexes of Mono‐Methyl Glutarate

The synthesis and characterization of some novel compounds of organotin(IV) chlorides with monomethyl glutarate is reported; the ligand molecule appears to be bound to the tin atom through the carbonyl oxygen. The results obtained through ¹H‐¹³C‐¹¹⁹Sn NMR, FT‐IR and ¹¹⁹Sn Mössbauer spectra show that the diorganotin(IV) complexes have hexacoordination with octahedral geometry. Biological screening of the complexes reveals that the diorganotin(IV) complexes show significant activity against all microorganisms.     

Self-assembly and characterization of a novel 2D network polymer containing a 60-membered organotin macrocycle

The reaction of 1-(4-carboxyphenyl)-5-mercapto-1 H-tetrazole with trimethyltin chloride in the presence of sodium ethoxide in benzene affords a novel 2D organotin network structure complex 1, which is an unusual organotin network containing a hexanuclear 60-membered organotin macrocycle. The complex has been characterized by elemental analysis, IR, and (1)H, (13)C, and (119)Sn NMR spectroscopy. Furthermore, we have also characterized the complex by X-ray crystallography.     

三[(甲基二苯硅基)亚甲基]锡羧酸酯的研究

为寻找高效低毒杀螨剂,报道了通过改变Sila-Torgue羧酸酯的结构,用一个苯基代替一个甲基,观察其对生物活性及其配位结构的影响.合成了十八 个三[(甲基二苯硅基)亚甲基]锡羧酸酯.     

Synthesis and <Emphasis Type="Italic">in vitro</Emphasis> Fungicidal Study of Organotin(IV) Complexes of Monomethyl Glutarate

The synthesis and study of new coordination compounds of some organotin(IV) chlorides with monomethyl glutarate are reported. The ligand molecule appears to be bound to the tin atom through the carboxylic oxygen. The results obtained from ¹H, ¹³C, and ¹¹⁹Sn NMR, FT-IR and ¹¹⁹Sn Mossbauer spectra show that the complexes are pentacoordinated with the trigonal bipyramidal structure. Biological screening of organotin(IV) derivatives shows promising activity, especially for the triphenyltin complex exhibiting higher antifungal activity. In addition, the rest of the compounds also prove to be active against various fungi used.     

Organotin perfluorooctanesulfonates as air-stable Lewis acid catalysts: synthesis, characterization, and catalysis

The reactions of 1,3-dichloro-1,1,3,3-tetrabutyldistannoxane and dialkyltin dihalides with silver perfluorooctanesulfonate provided the corresponding sulfonates as hydrates. The number of water molecules (n) of hydration was dependent on the conditions. The distannoxane derivative was identified as n from 0.5 to 6, while in the hydrated mononuclear species and DMSO complexes n varied widely from 4 to 13. 119Sn NMR spectroscopy and conductivity measurements indicated the ionic dissociation of these compounds in solution. These compounds exhibited unusually high solubility in polar organic solvents. The ionic dissociation together with facile hydration probably causes the unusual solubility. The Lewis acidity of these compounds was found to be high among organotin derivatives on the basis of ESR spectra of superoxide/metal-ion complexes. In contrast to well-known organotin triflates, these compounds suffered no hydrolysis upon storage in open air. The high catalytic activity of the distannoxane 1 was exemplified for various carbon-carbon bond-forming reactions, such as Mukaiyama-aldol as well as -Michael reactions and allylation of aldehydes.     

Complete 1H and 119Sn NMR spectral assignment for an asymmetric di[dihydroxotin(IV)] bis-porphyrin supramolecular host and its corresponding tetraacetato complex

The full (1)H and (119)Sn NMR spectral assignments for a di[dihydroxotin(IV)] bis-porphyrin supramolecular host I and for the di[diacetatotin(IV)] complex II are presented. Despite the lack of varied chemical functionality in these molecules, all of their 64 proton environments are non-equivalent. This is due to the asymmetry afforded by the Tr?ger's base (methanodiazocine) bridge between the porphyrin and quinoxalinoporphyrin macrocycles. The methanodiazocine bridge imparts chirality and concavity on the host framework and the quinoxalino link to one porphyrin macrocycle results in a negation of C(2) symmetry. The anisotropy of the aromatic porphyrin and quinoxalinoporphyrin macrocycles results in good dispersion for all 60 signals of the host framework and for the four ligands bound in the axial positions of the tin(IV) centres. The full assignment of the (1)H NMR spectra for these systems was achieved using dqf-COSY, NOESY, ROESY, (1)H-(119)Sn HMQC, (1)H-(13)C HSQC and (1)H-(13)C HMBC spectroscopy at temperatures that optimised dispersion. The (1)H-(119)Sn HMQC was particularly useful in this assignment. The (119)Sn chemical shift is sensitive to the functionality of the porphyrin and to the nature of the axial ligation, and the (119)Sn centre couples to both the ligand protons and the beta-pyrrolic protons. This allows unequivocal identification of the spin systems associated with each metal centre.     

三苯基锡—O,O—二芳基二硫代磷酸酯的合成和结构表征

本文合成了13种三苯基锡-O,O-二芳基二硫代磷酸酯,测定了它们的IR、~1H、~(31)C、~(119)SnNMR,MS和元素分析,结果表明该类化合物具有单体的四面体四价锡结构。     

三丁基锡烃氧(硫)乙酸盐的合成和除草活性测定

本文报道了13种三丁基锡烃氧(硫)乙酸盐的合成及其除草活性的初筛和复筛结果,讨论了化合物的IR和NMR谱,农药活性的测定结果表明,该类化合物的除草活性优于或接近除草剂2,4-D(2,4-二氟苯氧乙酸)。     

三烃基锡肟类化合物的合成及生物活性

共合成了１３个未见文献报道的三烃基锡肟衍生物，测定了它们的＾１ｈ，（＾１３Ｃ，＾１１９Ｓｎ）ＮＭＲ，ＩＲ和ＭＳ。结果表明此类化合物为四配位锡单体结构，生物活性测定结果表明部分化合物同时兼有杀菌、杀螨、除草多种活性。     

Synthesis characterization and biological study of diorganotin(IV) complexes of monomethyl phthalate

The synthesis and characterization of new coordination compounds of some organotin(IV) chlorides with monomethyl phthalate is reported; the ligand molecules appear to be bound to the tin atom through carbonyl oxygen atoms. Their structures have been characterized by elemental analyses, molar conductance, and bonding in these complexes is discussed in terms of their IR, (1)H, (13)C, (119)Sn NMR and (119 m)Sn M?ssbauer spectral studies. The spectroscopic results obtained are in full agreement with the proposed 2:1 stoichiometry. The complexes soluble in DMSO have been screened against a wide spectrum of bacteria and the results obtained are quite promising. The LD(50) values have also been determined in the albino rats. Some of the complexes also exhibit high anti-inflammatory activity.     

二氯马来酰亚胺有机锡化合物的合成和结构表征

合成了１４个１－三羟锡基－３，４－二氯马来酰亚胺有机锡化合物，研究了它们的核磁共振谱（＾１Ｈ，＾１３Ｃ，＾１１９Ｓｎ），外光谱质谱，并且得出，锡原子上的烃基对化合物的生物活性有很大的影响。     

119Sn Chemical Shifts in five- and six-coordinate organotin chelates

¹¹⁹Sn chemical shifts, δ(¹¹⁹Sn), relative to Me₄Sn in five- and six-coordinate organotin chelates were measured by means of FT NMR spectroscopy. ¹¹⁹Sn resonances were found to lie between ca. ?90 and ?330 ppm in the five-coordinate compounds and between ca. ?125 and ?515 ppm in the six-coordinate derivatives. thus δ(¹¹⁹Sn) moves upfield by 60–150 ppm with a change of the coordination number of tin from four to five and by 130–200 ppm from five to six. the δ(¹¹⁹Sn) values were shifted depending on the nature of chelating ligands and this shift was discussed in terms of the bonding between the ligand and tin. Replacement of methyl groups attached to tin by phenyl groups in five- and six-coordinate compounds induces upfield shifts in δ(¹¹⁹Sn) parallel to those found in four-coordinate organotin halides.     

New organotin carboxylates derived from 6-chloro-3-pyridineacetic acid exhibiting discrete molecular, drum-like, linear polymeric and ladder structures constructed from dimeric tetraorganodistannoxane units

Seven new organotin (IV) carboxylates have been synthesized by the reactions of 6-chloro-3-pyridineacetic acid with triorganotin chloride and diorganotin dichloride. All the complexes were characterized by elemental analysis, IR, ¹H NMR, ¹³C NMR, ¹¹⁹Sn NMR and X-ray crystallography. The structural analyses show that all the complexes present various structures, including monomer, drum, 1D polymers and ladders. It is worth noting that complex 1 is a novel 1D spring-like helical chain containing guest solvent molecules.     

Alkylchlorotins grafted to cross-linked polystyrene beads by a -(CH2)n- spacer (n=4, 6, 11): selective, clean and recyclable catalysts for transesterification reactions

Insoluble polystyrene grafted compounds of the type (P-H)(1-t){P-(CH2)n SnBu(p)Cl(3-p)}(t), (P-H)(1-t){P-(CH2)n SnBuO}(t) and (P-H)(1-t)[{P-(CH2)n SnBuCl}2O](t/2), in which (P-H) is a cross-linked polystyrene; n=4, 6, and 11; p=0 and 1; and t the degree of functionalisation, were synthesised from Amberlite XE-305, a polystyrene cross-linked with divinylbenzene. The compounds were characterised by using elemental analysis, and IR, Raman, solid-state 117Sn NMR, and 1H and 119Sn high-resolution MAS NMR spectroscopy. The influence of the spacer length and the tin functionality on the catalytic activity of these compounds, as well as their recycling ability, was assessed in the transesterification reaction of ethyl acetate with various alcohols. These studies showed significant differences in the activity of the catalysts interpreted in terms of changes in the mobility of the catalytic centres. Some of the supported catalysts could be recycled at least seven times without noticeable loss of activity. The residual tin content in the reaction products was found to be as low as 3 ppm.     

核磁共振方法表征2,2''''-二(对羧酸苯氧基)-1,1''''联萘

利用１Ｈ ＮＭＲ，１３Ｃ ＮＭＲ研究了 ２，２’－二（对羧酸苯氧基）－１，１’－联萘结构，并通过１Ｈ－１Ｈ ＣＯＳＹ及１３Ｃ－１Ｈ异核相关谱进一步确定了其１Ｈ谱和１３Ｃ谱中各谱峰的归属，为同类化合物的表征提供了一个依据。     

2,2'-二(对胺苯甲酯)-1,1'联萘的核磁共振谱解析

利用~1HNMR,~(13)CNMR谱研究了2,2’-二(对胺苯甲酯)-1,1’联萘的结构,并通过~1H-~1HCOSY,~(13)C-~1H异核相关及~(13)C-~1H异核远程相关谱进一步地确定了~1H谱和~(13)C谱中各谱峰的归属,为同类化合物的表征提供了一个依据.     

Multinuclear solid state NMR investigation of two polymorphic forms of ciprofloxacin-saccharinate

Two polymorphic forms of a novel pharmaceutical compound, ciprofloxacin-saccharinate (CIP-SAC), are analyzed using one dimensional (1D) and two dimensional (2D) (1)H nuclear magnetic resonance (NMR) at fast magic angle spinning (MAS). Additionally (15)N spectroscopy and (1)H-(13)C correlation experiments were performed to complement our conclusions. The 1D (1)H NMR spectra of CIP and complexes reveal valuable information about the ionic bonding between ciprofloxacin and saccharine. Additionally, these spectra allow us to perform a clear characterization of each solid form, giving the number of molecules per unit cell in one of the polymorphs. From 2D (1)H-(1)H spectra obtained through double quantum correlations we can arrive at important conclusions about the hydrogen bonding, conformation, and intra and inter-molecular interactions present in these compounds. Comparing and contrasting the (1)H-(1)H correlation data obtained for both polymorphic forms and taking into account the single crystal structure data existing for the solid form CIP-SAC (II) was possible to extract some conclusions on the polymorph CIP-SAC (I) where no single crystal information is available. (1)H MAS NMR is shown to be an important tool in the field of polymorphism and for the characterization of multicomponent pharmaceutical compounds.     

六氟磷酸二(2,2'-联吡啶)·(4,4'-二甲基-2,2'-联吡啶) 合钌(Ⅱ)的二维核磁共振谱分析

用一维NMR方法研究了电化学发光物质六氟磷酸二(2,2'-联吡啶)·(4,4'-二甲基-2,2'-联吡啶)合钌(Ⅱ)的立体结构,借助二维1H-1H COSY和1H-13C COSY实验技术对其氢谱和碳谱进行了完全的归属,并给出了其氢谱和碳谱的化学位移值.     

Synthese et etude par RMN 119Sn de nouveaux composes benzyliques organostanniques

Preparations of new benzylic organotin compounds are presented. ¹¹⁹Sn NMR studies show long range coupling constants ¹¹⁹Sn¹¹⁹Sn and intramolecular coordination of tin.