The reaction of perfluoroalkanesulfonyl halides Ⅶ. Preparation and reactions of trifluoromethanesulfonyl bromide

The reaction between sodium trifluoromethanesulfinate, which was prepared from trifluorome-thyl bromide, with bromine in aqueous solution resulted in the formation of trifluoromethanesulfonylbromide (CF_3SO_2Br). CF_3SO_2Br reacted with alkenes and alkyne to give the corresponding adductswith the loss of SO_2 in good yields, and with compounds containing active hydrogen to give brominatedderivatives. A radical reaction mechanism was proposed and confirmed by EPR study.     

The CO_2 laser-induced radical-chain reactions between CH_3CF_2H and chlorine-atom donors CF_2ClCFCl_2, CF_3CCl_3 CFCl_3 or CF_2Cl_2

The CO_2 laser induced room temperature reactions of CH_3CF_2H or another protium-donorCH_3CHClCH_3 with chlorine-atom donors (Z--Cl) CFCl_2CF_2Cl, CF_3CCl_3, CFCl_3 or CF_2Cl_2, havebeen investigated. Some of these reactions can yield two important monomers (CF_2=CH_2 andCF_2=CFCl) for fluoropolymers simultaneously. The yield dependence of these two alkenes on experi-mental conditions has been studied. A laser-initiated chain process is supported by identifica-tion of Z--H intermediates in these reactions.     

PERFLUORO-AND POLYFLUORO-SULFONIC ACIDS (ⅩⅤ)——GENERATION OF DIFLUOROCARBENE AND FLUOROSULFONYLDIFLUOROMETHIDE ION FROM METHYL α-FLUOROSULFONYLDIFLUOROACETATE

The decarbomethoxylation reactions of MeOCOCF_2SO_2F (1) can be induced readily by a varietyof nucleophiles. For example, X~- (Cr~-, Br~-, I~-), CNS~-, Et_3N, C_5H_5N make facile attack onmethyl carbon of 1 with subsequent elimination of CO_2, SO_2 and F~- resulting in generation of CF_2:. Innonaqueous organic solvents fragmentation of 1 was extremely fast and apparently might take place withsimultaneous elimination of SO_2 and F~- and formation of CF_2:. In aqueous organic solvents the inter-mediate FSO_2CF_2~- may be trapped by protonation into HCF_2SO_2F (2) as well as predominantly furthereliminate SO_2 and F~- yielding CF_2:. Alkoxide ions could not decompose 1 to produce CF_s:, but wereable to attack the sulfur atoms to afford the corresponding sulfonates, MeOCOCF_2SO_2Z (10) (Z=OCH_2-CF_2CF_2H, OC_6H_5). In the absence of solvent Et_2NH mainly induced the decomposition of 1 to form CF_2:with some attack on carboxyl carbon to give the corresponding amide FO_2SCF_2CONE_(t2).     

RELATIVE REACTIVITIES OF POLYHALOFLUOROALKANES TOWARD HALGPHILIC ATTACKS

Relative reactivities of polyhalofluoroalkanes toward bromophilic or chlorophilic attacks have been evaluated for the first time by comparing the rates of halophilic attacks by a carbanion derived from the addition of a nucleophile to an olefin with the rate of β-elimination of the same carbanion intermediate. Relative reactivity orders of some polybromofluoroalkanes and polychlorofluoroalkanes are CF_2Br_2>CF_3CFBr_2 ～ CF_2BrCF_2Br>CF_3CBr_3, and CCl_4 > CF_3CCl_3 > CF_2ClCCl_3 > CFCl_3 > CFCl_2CFCl2 ～ CF_2ClCFCl_2. Early transition states for halophilic attacks are speculated.     

在烷氧自由基的β-断裂中形成·CF_3和·CH_3的相对难易度研究

形成全氟烷基与碳氢烷基的相对难易度的直接比较问题,是一个根本性问题,但至今未获解决。我们用改进的方法成功地合成了新的次氯酸醋CF_3C(CH_3)_2OCl和CCl_3C(CH_3)_2OCl;又参照Kinillov方法,合成了新的二烷基过二碳酸酯(CF_3C(CH_3)_2OCO_2?_2,并对上述化合物在CCl_4溶液中的热分解反应进行了详细的研究。通过测定相应的烷氧自由基的β-断裂产物的方法,第一次可靠地给出了在烷氧自由基的β-断裂中,·CH_3与·CF_3,·CCl_3与·CH_3形成的相对难易度。     

The reaction of perfluoroalkanesulfonyl halides Ⅷ. A mild method for introducing BrCF_2 group to organic molecules

BrCF_2SO_2Br, prepared from sulfinatodehalogenation of CF_2Br_2 followed by bromination ofthe intermediate BrCF_2SO_2Na, was shown to be a mild and efficient bromodifluoromethylating agent.     

A NEW FACILE METHOD FOR THE SYNTHESIS OF AZACROWN ETHERS BY USING BENZYLSULFONAMIDE AS A SOURCE OF NITROGEN

Benzylsulfonamide was used as a source of nitrogen in the syn-thesis of azacrown ethers,and the cyclic intermediates were easily deben-zylsulfonylated by treating with CaF_2/H_2SO_4 to afford the azacrown ethers.     

利塞膦酸钠关键中间体3-乙酰基吡啶的合成

3-乙酰基吡啶是合成利塞膦酸钠的关键中间体.室温下,以3-乙炔基吡啶在CF_3SO_3H/CF_3CH_2OH(n(CF_3SO_3H)/n(CF_3CH_2OH)=20%)催化体系中顺利进行马氏水合反应,反应收率较高,环境友好,该方法同时具有原料易得、反应条件温和、操作简便、适合工业化生产等优点.     

全氟和多氟烷基磺酸的研究 ⅩⅧ.由二氟甲磺酰氟的衍生物产生二氟卡宾的研究

前文报道HCF_2SO_2F(1)与某些亲核试剂反应时会产生:CF_2,HCF_2SO_3H和P_2O_5,POCl_3等作用时也会形成:CF_2.本文报道二氟甲磺酸和磺酰胺在不同条件下产生:CF_2的结果. 我们在研究CH_3O_2CCF_2SO_3R(R=C_6H_5,HCF_2CF_2CH_2)的脱甲氧羰基反应时发现在质子溶剂(如ROH)中进行时得到HCF_2SO_3R.若用LiCl在HMPA/THF中与它反应,并加     

连续二氧化碳激光敏化氧化CF2HCL,CF2=CF2,CF2=CFCl,CHCl3,CHCl=CCl2和CH2=CH2

本文报道了连续二氧化碳激光敏化氧化CF_2HCl,CF_2==CF_2,CF_2==CFCL,CHCl_3,CHCl==CCl_2和CH_2==CH_2的反应,讨论了某些反应的机制。结果表明,激光敏化方法可以使不能直接吸收激光的反应物分子在气相中发生反应,并有可能产生卡宾。     

CX_3NO(X=H,F,Cl)分子结构稳定性的Ab initio研究

CH_3NO(1)、CH_2FNO(2)、CHF_2NO(3)、CH_2ClNO(4)、CHCl_2NO(5)、CHCIFNO(6)、CF_3NO(7)和CCl_3NO(8)是一类重要的光化学分子,它们稳定性差、寿命短,实验研究其结构及稳定性较困难,仅CH_3NO、CF_3NO和CCl_3NO分子有理论研究,其余均未见报道,本文用ab initio方法在STO-3G水平上研究了上述分子结构稳定性,还用STO/     

SYNTHESIS AND CHARACTERIZATION OF FOUR-ARMED BLOCK POLY(STYRENE-b-p-NITROPHENYL METHACRYLATE)PREPARED BY THE ATRP METHOD*

A novel tetrafunctional initiator, C [CH_2O (CH_2)_3 OOCCH(Br)CH_3]_4 (1), was synthesized through the reaction oftetraol with α-bromopropionyl chloride, and then was used as initiator of atom transfer radical polymerization (ATRP) in thepreparation of 4-armed polystyrene (PSt) with narrow polydispersity. The structure, molecular weight and molecular weightdistribution (MWD) of each arm were studied by ~1H-NMR and GPC data of hydrolyzed products of the 4-armed PSt. TheATRP of St using 1/CuBr/bpy as initiator system is of "living" character based on the following evidence: narrow MWD,constant concentration of chain radical during the polymerization, control of molecular weight by the molar ratio of monomerconsumed to 1. The 4-armed poly(St-b-p-nitrophenyl methacrylate) [poly(St-b-NPMA)] was prepared by the ATRP ofNPMA using 4-armed PSt with terminal bromine as the initiator, and characterized by FT-IR, ~1H-NMR spectra and GPCcurves. The micelles with PSt as core, and PNPMA as shell were formed by dropping DMSO into a solution of 4-armedpoly(St-b-NPMA) in DMF, as proved by laser light scatter (LLS) method.     

AN APPROACH TO SYNTHESIZE POLY(ETHYLENE GLYCOL)-b-POLY(ε-CAPROLACTONE) WITH TERMINAL AMINO GROUP via SCHIFF’S BASE AS AN INITIATOR

A new method to synthesize a degradable terminal amino group-containing copolymer,poly(ethylene glycol)-b- poly(ε-caprolactone)(MPEG-PCL-NH_2),was developed in the following three steps:(1)the ring-opening polymerization (ROP)ofε-caprolactone from the Schiff base prepared from benzatdehyde and ethanolamine(Ph-CH=NCH_2CH_2OH)used as an initiator to obtain heterobifunctional poly(ε-caprolactone)with one terminal Schiff base group and one hydroxyl group (HO-PCL-CH_2CH_2N=CH-Ph);(2)the coupling reaction of two reactive precursors,a hydroxy-terminated HO-PCL- CH_2CH_2N=CH-Ph andα-monocarboxy-ω-monomethoxy poly(ethylene glycol)(CMPEG)to synthesize MPEG-PCL- CH_2CH_2N=CH-Ph;(3)the conversion of the -N=CH-Ph end-group into NH_2 end-group by acidification of acetic acid to obtain MPEG-PCL-NH_2.The structures from the precursors to the terminal amino group-containing copolymer were confirmed by ~1H-NMR and their molecular weights were measured by gel permeation chromatography.The amphiphilic terminal amino group-containing copolymer could self-assemble into micelles in an aqueous system with PCL block as the core and PEG block as the shell.The micelle formation of the terminal amino group-containing block copolymer was studied by fluorescent probe technique and the existence of critical micellar concentration(cmc)confirmed the amphiphilic nature of the resulting copolymer.ESEM and DLS analysis of the micelles revealed a homogeneous spherical morphology and a unimodal size distribution.     

RADICAL PHOTOPOLYMERIZATION USING ARYLIODONIUM SALT/TERTIARY AMINE COMPLEX SYSTEM AS THE PHOTOINITIATOR

The diphenyliodonium salt (DPIOC)/triethylamine (TEA) is used as photoinitiator for radical photopolymerization. It was found that a ground state CT complex formed between DPIOC as electron acceptor and TEA as electron donor, which results in extending the photosensitivity range of DPIOC/TEA system up to above 500nm compared with DPIOC alone. The kinetic studies on photopolymerization of methyl methacrylate (MMA) were carried out in CH_3CN: H_2O (14: 1, v/v) mixture solution at 30℃by dilatometer. The results obtained show that the polymerization rate (R_p) increases with increasing concentrations of DPIOC and TEA with exponent 0. 65 and 0. 62 respectively. The activation energy E_a and k_p/k_~(1/2) value were determined to be 4.1 Kcal mol~(-1) and 0.045 respectively. The other influence factors and reaction mechanism were also discussed.     

7-Deazapurines:Synthesis of new pyrrolo[2,3d]pyrimidin-4-onescatalyzed by a Brφnsted-acidic ionic liquid as a green and reusable catalyst

<正>Some new 2-aryl-3,7-dihydro-4H-pyrrolo[2,3-d]pyrimidin-4-ones have been prepared through cyclocondensation of 2-amino 1H-pyrrole-3-carboxamides with aromatic aldehydes followed by air oxidation in the presence of 3-methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate[(CH_2)_4SO_3HMIM][HSO_4],a Br(?)nsted-acidic ionic liquid,as a green and reusable catalyst in solvent-free conditions.     

氟烷基化和氟烷氧基化的研究——5.苯基硫酚阴离子与5-卤-3-氧杂全氟戊基二乙基磺酰胺的反应

本文研究了X(CF_2)_nI(X=H,F,Cl,Br,I),I(CF_2)_2O(CF_2)_2SO_2NEt_2,R_1CF_2Br,Br(CF_2)_2O(CF_2)_2SO_2NEt_2与PhSNa的S_(RN)l反应。这个反应不仅易于发生,而且苯基硫酚阴离子单取代产物或二取代产物的产率较高。苯基硫酚阴离子与ω-H,ω-Cl全氟烷羟并不发生反应。Cl_2CYCF_2O(CF_2)_2SO_2NEt_2(Y=Cl,F)也易与PhSNa反应,并且还发生C—O断裂得PhSCF_2-CYClH、PhSCF_2CYCl_2、PhSCF—CYCl和(PhS)_2C—C(SPh)_2,PhSCOCF_2SO_2NEt_2,估计反应是通过阴离子型链式机理。     

全氟和多氟烷基磺酸的研究——ⅩⅤ.由α-氟砜基二氟甲基乙酸甲酯形成二氟卡宾和氟砜基二氟甲基阴离子

FO_2SCF_2CO_2CH_3(1)和许多亲核试剂作用时很容易发生脱羧甲基分解反应。例如X~-(Cl~-,Br~-,I~-)CNS~-,Et_3N,C_5H_5N等都可以进攻其甲基碳,接着消去CO_2,SO_2和F~-而产生:CF_2。在非水有机溶剂中,脱羧后极快地同时消去SO_2,F~-形成:CF_2;但在含水有机溶剂中,则先形成中间体FO_2SCF_2~-,它可被质子捕获生成HCF_2SO_2F(2)。大部分仍继续消除SO_2和F~-产生:CF_2。烷氧阴离子不能类似地将1分解,而是进攻1的硫原子得到相应的磺酸酯CH_3O_2CCF_2SO_2—Z(10)(Z=OCH_2CF_2CF_2H,OC_6H_5)。在无溶剂情况下,Et_2NH也能使1分解而形成:CF_2,还伴有少量进攻羧基碳的产物FO_2SCF_2CONEt_2(11)。     

有机氟化学的新进展

本文综述氟有机化学的最新进展。论及:1.气溶胶直接氟化法,新的温和的氟化试剂——CH_3CO_2F,N-氟代二氢吡咯酮,R_F(?)(C_6H_5)CF_3SO_3(?)和喷雾干燥的KF。2.合成全氟烷基磺酸的新方法,如全氟烷基碘在金属活化下与SO_2在DMF中的反应,又如I(CF_2)_2O(CF_2)_2SO_2F与C_2F_4调聚和全氟卤代烷的亚磺化脱碘反应。3.惰性—CF_2—及—CF_3的新反应,如五氟一氯丙酮与KF的反应,多氯氟乙烷与硫酚钠的反应。4.具有生理活性的氟化物,如抗癌物fluorosesqisiloxane,杀虫剂29-fluorositosterol。     

铜参与的1,1,1-三氟-2,2-二氯乙烷及1,1,1-三氟-2,2,2-三氯乙烷与苯乙烯的加成反应研究

该反应为铜/联吡啶调控的CF_3CHCl_2及CF_3CCl_3对苯乙烯化合物的原子转移自由基加成反应.该反应通过添加联吡啶来增强铜的还原性,成功实现了CF_3CHCl_2和CF_3CCl_3较惰性C—Cl键的断裂,并与烯烃生成单一的自由基加成产物.     

Product yields of stabilized Criegee intermediates in the ozonolysis reactions of cis-2-butene, 2-methyl-2-butene,cyclopentene, and cyclohexene

Cavity ring-down spectroscopy(CRDS)was utilized in combination with chemical titration with sulfur dioxide(SO_2)to quantify stabilized Criegee intermediates(s CIs)produced at low pressures(4–20 Torr)in ozonolysis reactions of cis-2-butene,2-methyl-2-butene,cyclopentene,and cyclohexene.The yield of stabilized s CI,acetaldehyde oxide(CH_3CHOO),from cis-2-butene ozonolysis decreased with decreasing pressure and reached to 0.05±0.04 at the zero-pressure limit.The nonsymmetric alkene 2-methyl-2-butene produced two stabilized s CIs,CH_3CHOO and acetone oxide((CH_3)_2COO),and their total yield decreased with decreasing pressure and reached 0.01±0.03 at the zero-pressure limit.For cyclopentene and cyclohexene,the s CI yields were essentially constant near zero,as expected of endocyclic alkenes.The nascent yields of s CI of various alkenes are compared.