3—烷氧基—2—羟基丙基—三甲基溴化铵的表面活性和加溶作用

３－烷氧基－２－羟基丙基－三甲基溴化铵同系物的表 力以及对甲基黄的增溶能力。结果表明,同系物随碳原子增加表面活性增强,对甲基黄的增溶能力亦增强。     

3-烷氧基-2-羟基丙基三甲基氯化铵和十二烷基磺酸钠混合溶液的相互作用

研究了3-烷氧基-2-羟基丙基三甲基氯化铵（RTAC）同系物与十二烷基磺酸钠（R12SO3Na）混合水溶液的表面张力、胶团形成和表面吸附。实验表明,此类复配体系在胶团形成,降低表面张力的效率和能力上均显示了全面的增效作用。     

Poly‐α,β‐(3‐hydroxypropyl)‐DL‐aspartamide: A new drug carrier

Poly‐α,β‐(3‐hydroxypropyl)‐DL ‐aspartamide (PHPA) was synthesized by the ring‐open reaction of polysuccinimide (PSI) and 3‐hydroxypropylamine. The polymer was characterized by ¹H‐NMR, ¹³C‐NMR, FTIR, and GPC. Mark–Houwink coefficients were obtained from viscometry and GPC measurements, K = 5.53 × 10⁻³ and α = 0.78 in water. The acute toxicity of PHPA was examined and it revealed no death in ICR mice up to the dose treated of 15.3 kg/kg, and hematological parameters showed no significant difference between treated and control animals. The potential use of PHPA as a drug carrier was also investigated. In a typical case, a contraceptive drug, norethindrone (NET), was bonded to PHPA, and the drug sustained released as long as 120 days an in vitro test. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2411–2417, 2000     

盐酸返滴定测定3-氯-2-羟丙基三甲基氯化铵含量的方法研究

3-氯-2-羟丙基三甲基氯化铵是一种重要的有机原料。本文对采用盐酸返滴定测定其含量的方法进行了研究,样品在40±1℃的水浴中与过量的氢氧化钠标准溶液反应35分钟后,以甲基红为指示剂,用盐酸标准溶液返滴定剩余的氢氧化钠,从而得到3-氯-2-羟丙基三甲基氯化铵的含量。实验表明,这种方法操作简单、测定快速、准确度高、重现性好。     

Retention of Eucalyptol,a Natural Volatile Insecticide,in Delivery Systems Based on Hydroxypropyl‐β‐Cyclodextrin and Liposomes

Eucalyptol (Euc) is a natural monoterpene with insecticide effects. Being highly volatile and sensitive to ambient conditions, its encapsulation would enlarge its application. Euc‐loaded conventional liposomes (CL), cyclodextrin/drug inclusion complex, and drug‐in‐cyclodextrin‐in‐liposomes (DCL) are prepared to protect Euc from degradation, reduce its evaporation, and provide its controlled release. The liposomal suspension is freeze‐dried using hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD) as cryoprotectant. The liposomes are characterized before and after freeze‐drying. The effect of Euc on the fluidity of liposomal membrane is also examined. A release study of Euc from delivery systems, in powder and reconstituted forms, is performed by multiple head extraction at 60 °C after 6 months of storage at 4 °C. CL and DCL suspensions are homogeneous, show nanometric vesicles size, spherical shape, and negative surface charge before and after freeze‐drying. Moreover, HP‐β‐CD does not affect the fluidity of liposomes. CL formulations present a weak encapsulation for Euc. The loading capacity of eucalyptol in DCL is 38 times higher than that in CL formulation. In addition, freeze‐dried DCL and HP‐β‐CD/Euc inclusion complex show a higher retention of eucalyptol than CL delivery system. Both carrier systems HP‐β‐CD/Euc and Euc‐loaded DCL decrease Euc evaporation and improve its retention. Practical Applications: Eucalyptol is a natural insecticide. It is highly volatile and poorly soluble in water. To enlarge its application, its encapsulation in three delivery systems (conventional liposomes, cyclodextrin/drug inclusion complex, combined system composed of cyclodextrin inclusion complex and liposome) is studied. In this paper it is proved that cyclodextrin/eucalyptol inclusion complex and eucalyptol‐in‐cyclodextrin‐in‐liposome are effective delivery systems for encalyptol encapsulation, retention, and release.     

Using hydroxypropyl‐β‐cyclodextrin for the preparation of hydrophobic poly(ketoethyl methacrylate) in aqueous medium

This work was committed to the polymerization of hydrophobic ketoethyl methacrylate monomer in aqueous medium in the presence of cyclodextrin, instead of polymerizing the monomer in toxic and volatile organic solvents. For this purpose, a new ketoethyl methacrylate monomer, p‐methylphenacylmethacrylate (MPMA), was synthesized from the reaction of p‐methylphenacylbromide with sodium methacrylate in the presence of triethylbenzylammonium chloride. The monomer was identified with FTIR, ¹H and ¹³C‐NMR spectroscopies. Hydroxypropyl‐β‐cyclodextrin (HPCD) was used to form a water‐soluble host/guest inclusion complex (MPMA/HPCD) with the hydrophobic monomer. The complex was identified with FTIR and NMR techniques and polymerized in aqueous medium using potassium persulfate as initiator. During polymerization the resulting hydrophobic methacrylate polymer precipitated out with a majority of HPCD left in solution and a minority of HPCD bonded on the resulting polymer. The thus‐prepared polymer exhibited little difference from the counterparts obtained in organic solvent in number average molecular weight (M_n), polydispersity (M_w/M_n) and yield. The investigation provides a novel strategy for preparing hydrophobic ketoethyl methacrylate polymer in aqueous medium by using a monomer/HPCD inclusion complex. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis of the Ammonium Salt of 6‐Amino‐2‐hydroxy‐ 3,5‐dinitropyrazine and a Comparison of its Properties with those of Ammonium 3,5‐Diaminopicrate (ADAP)

The ammonium salt of 6‐amino‐2‐hydroxy‐3,5‐dinitropyrazine has been synthesised from 2,6‐dimethoxy‐3,5‐dinitropyrazine and its properties (DSC, crystal structure, impact sensitiveness and thermochemical properties) are compared with the analogous benzene derivative, ammonium 3,5‐diaminopicrate.     

A Practical Synthesis of α‐Fluoroketones in Aqueous Media by Decarboxylative Fluorination of β‐Ketoacids

A practical and novel process for the decarboxylative fluorination of β‐ketoacids in water in the presence of phase transfer catalyst has been developed, affording a series of α‐fluoroketones in good to excellent yields. Furthermore, a preliminary investigation for the catalytic asymmetric transformation was performed and a proposed mechanistic pathway for this catalytic process was proposed.

     

Fourier transform infrared photoacoustic studies of the adsorption behavior of poly(2‐hydroxypropyl methacrylate) at solid–liquid interface

Adsorption of poly(2‐hydroxypropyl methacrylate) on alumina from dimethylformamide was studied by ultraviolet (UV) and Fourier transform infrared (FT‐IR) photoacoustic spectroscopy (FTIR PA) techniques. Adsorbent amount and concentration effects were investigated. The adsorption results are in conformity with Langmuir's isotherm. The differences observed in Langmuir parameters were explained by polymer–polymer, polymer–solvent, polymer–adsorbent, and solvent–adsorbent interactions. The fraction of carbonyl groups attached to the surface of alumina was calculated with a curve‐fitting computer program. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2750–2756, 2002     

Highly Enantioselective Phase‐Transfer Catalytic α‐Alkylation of α‐tert‐Butoxycarbonyllactams: Construction of β‐Quaternary Chiral Pyrrolidine and Piperidine Systems

A new enantioselective α‐alkylation of α‐tert‐butoxycarbonyllactams for the construction of β‐quaternary chiral pyrrolidine and piperidine core systems is reported. α‐Alkylations of N‐methyl‐α‐tert‐butoxycarbonylbutyrolactam and N‐diphenylmethyl‐α‐tert‐butoxycarbonylvalerolactam under phase‐transfer catalytic conditions (solid potassium hydroxide, toluene, −40 °C) in the presence of (S,S)‐3,4,5‐trifluorophenyl‐3,3′,5,5′‐tetrahydro‐2,6‐bis(3,4,5‐trifluorophenyl)‐4,4′‐spirobi[4H‐dinaphth[2,1‐c:1′,2′‐e]azepinium] bromide [(S,S)‐NAS Br] (5 mol%) afforded the corresponding α‐alkyl‐α‐tert‐butoxycarbonyllactams in very high chemical (up to 99%) and optical yields (up to 98% ee). Our new catalytic systems provide attractive synthetic methods for pyrrolidine‐ and piperidine‐based alkaloids and chiral intermediates with β‐quaternary carbon centers.     

C‐3 Selective Ring Opening of 2,3‐Aziridino Alcohols and their Derivatives with Nucleophiles in the Presence of β‐Cyclodextrin in Water

For the first time a mild and efficient procedure has been developed for the C‐3 selective ring opening, under biomimetic conditions, of 2,3‐aziridino alcohols and their derivatives with nucleophiles such as aromatic thiols and amines catalyzed by β‐cyclodextrin in water at room temperature to afford the corresponding β‐amino sulfides and diamines with high regioselectivity in impressive yields. The use of cyclodextrin precludes the use of either acid or base and the catalyst can be recovered and reused.     

Novel Aqueous Phase Supramolecular Synthesis of 3‐Pyrrolylindolin‐2‐ones and Pyrrolylindeno[1,2‐b]quinoxalines

Various 3‐pyrrolylindolin‐2‐ones and pyrrolylindeno[1,2‐b]quinoxaline were synthesized for the first time in high yields in water under neutral conditions by supramolecular catalysis involving β‐cyclodextrin. The β‐cyclodextrin can be recovered and reused a number of times without any loss of activity.     

Analysis of the reaction course of oxamide and N,N′‐bis(2‐hydroxypropyl)oxamide with propylene carbonate

Studies on obtaining and hydroxypropyl properties of oxamide (OD) derivatives with contribution of OD and N,N′‐bis(2‐hydroxypropyl)oxamide (BHPOD) were carried out. As a hydroxyalkylating agent, the propylene carbonate (PC) was used. Hydroxypropylating with OD proceeds with a partial preservation of carbonate groups in the structure of products, and during the reaction, a partial dimerization of hydroxypropoxylene derivatives of OD occurs. The obtained hydroxypropoxy derivatives of OD are distinguished by an increased thermal stability. Hydroxypropoxy derivatives of OD are expected to find application as polyol components for the manufacture of thermally stable foamed polyurethane plastics. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Synthesis of Thiiranes from Oxiranes in the Presence of β‐Cyclodextrin in Water

A mild and highly efficient, user‐friendly procedure has been developed for the conversion of oxiranes to thiiranes under supramolecular catalysis in the presence of β‐cyclodextrin in water at ambient temperature in excellent yields. The use of β‐cyclodextrin in this transformation overcomes the use of heavy metal halides as promoters and chlorinated hydrocarbons and other hazardous organic solvents.     

Negative effect of stretching on the development of β‐phase in β‐nucleated isotactic polypropylene

On the premise that shear in the slit die of an extruder was minimized as far as possible, β‐nucleated isotactic polypropylene (iPP) was extruded. Simultaneously, once the extrudate (in the melt state) left the die exit, it was stretched at various stretching rates (SRs). For iPP with a low content of β‐nucleating agent (β‐NA), the crystallinity of β‐phase (X_β) initially increases with increasing SR, and then decreases slightly with further increase in SR. However, for iPP containing a higher content of β‐NA, with increasing SR, X_β decreases monotonically, indicating a negative effect of SR on β‐phase formation. Small‐angle X‐ray scattering and polarized optical microscopy experiments reveal that, when SR is less than 30 cm min^?1, the increasing amount of row nuclei induced by increasing SR is mainly responsible for the increase of X_β. In contrast, when SR exceeds 30 cm min^?1, the overgrowth of shish structures unexpectedly restrains the development of β‐phase, and spatial confinement is considered as a better explanation for the suppression of β‐phase. Copyright © 2011 Society of Chemical Industry     

Palladium‐Catalyzed Efficient and One‐Pot Synthesis of Diarylacetylenes from the Reaction of Aryl Chlorides with 2‐Methyl‐3‐butyn‐2‐ol

An efficient and practical synthetic method has been developed for the preparation of symmetrical diarylacetylenes from the direct reaction of aryl chlorides with 2‐methyl‐3‐butyn‐2‐ol catalyzed by palladium(II) chloride‐bis(tricyclohexylphosphine) [PdCl₂(PCy₃)₂] under mild reaction conditions. Unsymmetrical diarylated acetylenes could be also obtained by using two different aryl chlorides simultaneously. The catalytic procedure includes a novel one‐pot palladium‐catalyzed, double Sonogashira coupling of inactivated aryl chlorides without use of copper(I) as co‐catalyst.     

Preparation of Nano‐Sized Copper β‐Resorcylate (β‐Cu) and its Excellent Catalytic Activity for the Thermal Decomposition of Ammonium Perchlorate

Copper β‐resorcylate (cupric 2,4‐dihydroxy‐benzoate, β‐Cu) nanoparticles were prepared at a large‐scale via a facile wet mechanical grinding method and vacuum freeze‐drying process. The as‐prepared β‐Cu nanoparticles were characterized by powder X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier‐transform infrared spectroscopy (FT‐IR). The results revealed that the nano‐sized β‐Cu is of semi‐spherical shape and of homogeneous distribution, with a fairly uniform size of 100 nm. The formation mechanism of β‐Cu nanoparticles in the whole process was discussed in detail. Furthermore, the catalytic properties of as‐obtained β‐Cu were investigated. The TG/DSC study showed that nano‐sized β‐Cu could be a promising additive for accelerating the thermal decomposition of ammonium perchlorate (AP).     

Synthesis of Nano‐γ‐Ferric Oxide by Thermolysis of the 2‐Mercapto‐5‐Methylpyridine‐N‐Oxide‐Iron(III) Complex via Factorial Design

2‐Mercapto‐5‐methylpyridine‐N‐oxide (MMPNO) and its sodium salt (NaMMPNO) were synthesized. The reaction of the latter with Fe³⁺ generates Fe(MMPNO)₃ chelate. The thermolysis of this chelate at 350 °C yielded highly pure reddish‐brown γ‐Fe₂O₃ nanocrystallites with an average particle size of 6.2 nm, a particle size range of 4.2 to 14.8 nm, and a specific surface area of 51.5 m²g^–1. The thermolysis process was optimized using the 2² fractional design. Quantitative tests and characterization of products were carried out by UV‐vis spectroscopy, XRD, LLS, SEM, TGA, BET, TEM, FT‐IR, elemental microanalysis, and classical analytical measurements.     

One‐Pot Double Benzylation of 2‐Substituted Pyridines using Palladium‐Catalyzed Decarboxylative Coupling of sp2 and sp3 Carbons

An efficient and practical decarboxylative double benzylation method for various 2‐picolinic acids has been established by using a bimetallic catalytic system of palladium(II) chloride (PdCl₂) and silver(I) oxide (Ag₂O), which offered a variety of diarylmethane derivatives with moderate to good yields.

     

Viscometric Study of the Inclusion Complex Between β‐Cyclodextrin and HTAC in Aqueous Solution

The inclusion complex formed by β‐cyclodextrin (β‐CD) with the cationic surfactant hexadecyltrimethylammonium chloride (HTAC) was studied by viscometry using poly(ethylene oxide) (PEO)–HTAC aggregates as a viscosity indicator. The relative viscosity of β‐CD in aqueous PEO–HTAC solution profiles shows that the formation of the β‐CD/HTAC inclusion complex causes HTAC molecules to be stripped off the PEO chains, resulting in a decrease of aqueous solution viscosity as a result of the decrease in electrostatic repulsion between polymer‐bound HTAC micelles. The viscosity minimum at C_β‐CD/C_HTAC = 0.5 indicates that the molecular ratio of host molecule to guest molecule is 1:2 in the β‐CD/HTAC inclusion complex.