有机磷化合物研究 ⅩⅧ.α-砜基膦酸酯的合成和反应

本文报道α-砜基碳阴离子和磷酰氯的反应,提供了合成α-砜基膦酸酯和α,β-不饱和砜的新方法,此方法具有原料易得、反应步骤少、得率较高等优点。还讨论了α-芳砜基膦酸酯的质谱。     

有机磷化合物研究XVIII α-砜基膦酸酯的合成和反应

本文报道α-砜基碳阴离子和磷酰氯的反应,提供了合成α-砜基膦酸酯和α,β-不饱和砜的新方法,此方法具有原料易得、反应步骤少、得率较高等优点.还讨论了α-芳砜基膦酸酯的质谱.     

具有生物活性的有机磷化合物的研究V.α—[（取代）芳氧基乙酰氧基]烷基膦酸

通过取代苯氧乙酰氯和α－羟基烷基膦酸酯的缩合反应合成了８种标题化合物，用元素分析，红外，核磁及质谱作了表征，测定了它们的除草活性和植物生长调节活性。     

α-氨基膦酸酯衍生物的合成及其表征

合成了一系列N端含有均三唑并噻二唑的α-氨基膦酸酯衍生物, 其结构经过红外、核磁共振氢谱、磷谱、质谱和高分辨质谱等确证.     

α-羟基膦酸酯芳甲酸酯的合成、晶体结构和质谱裂解规律研究

α-羟基膦酸酯与各种取代苯甲酸或吡啶甲酸,通过酰氯或缩合剂的作用,合成了一系列的O,O-二烷基-α-苯基-α-(取代芳基甲酸酯基)-甲基膦酸酯的衍生物.它们的合成收率为61%～84%,这些化合物的结构经过核磁(1HNMR,13CNMR和31PNMR)、红外、质谱、元素分析或高分辨质谱确证,同时化合物C1的结构在晶体结构解析上进一步得到证实.利用多级质谱分析了化合物C2,C5和C8的质谱裂解规律,解释了重排离子的形成机制.     

a-（取代苯氧基苯甲酰氧基）烃基膦酸酯的合成方法

采用两种合成路线来合成O，O-二乙基-a-(2-氯-4-三氟甲基苯氧基苯甲酰氧基)丙基膦酸酯，并对其结果进行了比较分析，以此来探讨a-(取代苯氧基苯甲酰氧基)烃基膦酸酯的合成方法。     

N－三苯锗丙酰基－α－氨基膦酸酯的合成及其性质研究

合成了两个系列含有三苯锗丙酰基的α－氨基膦酸酯类化合物，研究了空阻大的α－氨基膦酸酯与β－三苯锗丙酸的缩合方法、反应条件及反应机理．生物活性测定结果表明，这类衍生物与相应的α－氨基膦酸衍生物相比有显著抗癌活性和抗烟草病毒活性。     

3-烷基膦酸酯基取代的异吲哚啉酮衍生物的合成及生物活性

通过邻溴芳香亚胺的锂化及与一氧化碳的环化反应,随后与溴代烷基膦酸酯的"一锅法"反应,合成了一系列3-烷基膦酸酯基取代的异吲哚啉酮衍生物.利用核磁共振波谱及高分辨质谱对其结构进行了表征.初步的生物活性测试结果表明,部分化合物表现出明显的离体抗真菌活性.     

高立体选择性合成环氧乙烷-2-膦酸酯的研究

利用铑(Ⅱ)催化重氮苄基膦酸酯与芳香醛或酮化学专一地进行环氧化反应,高产率、高立体选择性地合成了顺式环氧乙烷-2-膦酸酯.反应历程是重氮化合物先与醛或酮形成羰基叶立德中间体,然后发生自身环化反应.产物经红外光谱、1H核磁共振谱、质谱和X射线衍射确定结构.     

光学活性α-羟基磷酸酯的合成

扼要综述了近年来关于光学活性α一羟基膦酸酯的新合成方法,介绍了有关的手性试剂和不对称反应。关键词##4光学活性;;α-羟基膦酸酯;;不对称合成     

芳香环状低聚物组分分布与单体结构关系的研究

根据Jacoson-Stockmayer(J-S)环化理论,应用基质辅助激光解吸离子化飞行时间质谱(MAIDL-TOFMS),对一系列芳香环状低聚物组分分布进行分析,研究了芳香环状低聚物的组分分布与单体结构的关系,结果表明,在芳香聚酯、聚膦酸酯及芳香聚醚环状低聚物系列中,Incn与Inn呈良好的线性关系,符合J-S理论分布,在环状聚酯及聚膦酸酯系列中,低聚物的组分分布受双酚单体的中心键角影响,单体的中心键角在100°～120°之间,其中心键角愈小,γ值愈大,而在聚醚系列中,在固定一种单体的前提下,环化物的组分分布受另一单体键角的影响与环状聚酯和聚膦酸酯相一致.     

An efficient preparation of isosteric phosphonate analogues of sphingolipids by opening of oxirane and cyclic sulfamidate intermediates with alpha-lithiated alkylphosphonic esters

D-erythro-(2S,3R,4E)-Sphingosine-1-phosphonate (1), the isosteric phosphonate analogue of naturally occurring sphingosine 1-phosphate (1a), and D-ribo-phytosphingosine 1-phosphonate (2), the isosteric phosphonate analogue of D-ribo-phytosphingosine-1-phosphate (2a), were synthesized starting with methyl 2,3-O-isopropylidene-d-glycerate (4) and D-ribo-phytosphingosine (3), respectively. Oxirane 12 was formed in eight steps from 4, and cyclic sulfamidate 22 was formed in five steps from 3. The phosphonate group was introduced via regioselective ring-opening reactions of oxirane 12 and cyclic sulfamidate 22 with lithium dialkyl methylphosphonate, affording 13 and 23, respectively. The synthesis of 1 was completed by S(N)2 displacement of chloromesylate intermediate 14b with azide ion, followed by conversion of the resulting azido group to a NHBoc group and deprotection. The synthesis of 2 was completed by cleavage of the acetal, N-benzyl, and alkyl phosphonate ester groups.     

芳香环状聚膦酸酯齐聚物的基质辅助激光解吸电离飞行时间质谱分析

用基质辅助激光解吸电离飞行时间质谱方法对一系列芳香环状聚膦酸酯低聚物进行了结构分析。比较了不同基质及阳离子剂对芳香环状聚膦酸酯分析结果的影响。1,8,9-蒽三酚基质仅对含有羰基基团聚膦酸酯环状齐聚物分析有效,而视黄酸基质则对所有聚膦酸酯环状剂聚物有效,是这类新型芳香环状齐聚物的适宜基质。环状聚膦酸酯齐聚物的阳离子齐分析表明,氯化锂是这种环状齐聚物的适宜的阳离子添加剂。     

SYNTHESIS, CHARACTERIZATION AND RING-OPENING POLYMERIZATION OF CYCLIC (ARYLENE PHOSPHONATE) OLIGOMERS

INTRODUCTIONThe use of cyclic oligomers as macrocyclic precursors for the preparation of high performance polymers byring-opening polymerization (ROP) has sparked much interest in recent years. It could produce a revolutionarychange in the preparation of advanced composite materials, and is of great importance in the polymerizationprocess yielding polymers such as the reinforced reactive injection model (RRIM) and the resin transfer model(RTM) etc. Within the last 10 years, the synthes…     

Substituent effects of phosphonate groups electronic repartition of π-conjugated ferrocene analogues of stilbene

The synthesis of para-substituted ferrocene analogues of stilbene was performed by using the Heck reaction, starting from vinylferrocene. The variation of the electronic density of these compounds with the electronic withdrawing strength of the substituents was studied using ¹³C NMR spectroscopy, absorption spectra and cyclic voltammetry. The correlation of Hammett constants with the redox properties of the substituted compounds using Nagy's method allowed us to revisit the determination of the Hammett constants of diethyl phosphonate ester and phosphonic acid substituents. Our measurements were in agreement with the literature except for the diethyl phosphonate group.     

无溶剂条件下α-羟基磷酸酯的合成

在无溶剂条件下,以碳酸钾做催化剂,芳香醛与亚磷酸酯在室温下通过研磨,合成了一系列磷酸酯类化合物.该反应条件温和,操作简单,时间短,对环境友好,是一种绿色的合成方法.产物结构经IR,MS,1HNMR等方法表征.     

Photochemical generation of difluoromethyl radicals having various functional groups and their highly regioselective addition to olefins and aromatic substitution

Difluoromethyl radicals bearing ester, phosphonate, nitrile, cyclic carbonate, and carbamate groups were generated by the photoinitiated S-CF₂ bond cleavage of electrosynthesized α,α-difluorosulfides, and their addition to olefins and aromatic substitution were successfully carried out to provide the regioselective adducts and substitution products in moderate yields. The yields of substitution products increased by the addition of diphenyl diselenide and 2,4,6-trimethylpyridine.     

Ready Access to Fluorinated Phosphonate Mimics of Secondary Phosphates. Synthesis of the (alpha,alpha-Difluoroalkyl)phosphonate Analogues of L-Phosphoserine, L-Phosphoallothreonine, and L-Phosphothreonine

In addition to the previously recorded reactions of diethyl lithio(difluoromethyl)phosphonate (8) with primary triflates and aldehydes, we report here that 8 reacts with functionalized, but unactivated, methyl esters to give efficient acyl substitution. Thus, 8 reacts cleanly (-78 degrees C, THF) with the following methyl esters (product, yield): methyl (S)-isopropylideneglycerate (14, 99%), methyl (S)-3-O-(tert-butyldimethylsilyl)-2 -O-tetrahydropyranylglycerate (16, 85%), and the Garner ester derived from D-serine (15, 77%). Expeditious treatment of the resultant alpha,alpha-difluoro-beta-keto phosphonates with hydride or Grignard reagents followed by alcohol deoxygenation provides a general method for the synthesis of (alpha,alpha-difluoroalkyl)phosphonate analogues of secondary phosphates. For tertiary alcohols, Dolan-MacMillan deoxygenation conditions are employed. The requisite methyl oxalate esters are obtained by an improved procedure wherein the lithium alkoxide of the hindered tertiary alcohol is irreversibly generated at low temperature and then condensed with methyl oxalyl chloride. Relative stereochemistry is assigned via conversion of the Garner ester derived Boc-amino alcohols to the corresponding cyclic, six-membered phosphonate esters and examination of their (1)H NMR spectra. The relevant vicinal coupling constants are extracted from these spectra by performing double quantum-filtered phase-sensitive COSY experiments. This new (difluoromethylene)phosphonate anion-methyl ester condensation, Grignard (hydride) addition, deoxygenation sequence has been applied to the synthesis of (alpha,alpha-difluoroalkyl)phosphonate analogues of L-phosphoserine (>/=96% ee) and L-phosphoallothreonine (93% ee) from D-serine and of L-phosphothreonine (91% ee) from L-glycerate, respectively.     

Properties of polyethylene modified with phosphonate side groups. I. Thermal and mechanical properties

Low-density polyethylene was modified by the inclusion of phosphonate ester pendent groups by using an oxidative chlorophosphonylation reaction followed by esterification of the polyethylene poly(phosphonyl chloride) with an alcohol. Two different types of phosphonate esters were prepared: dimethyl phosphonate from the reaction with methanol and a phosphonate graft copolymer from the reaction with hydroxy-terminated poly(ethylene oxide) (PEO). For the latter, oligomers with molecular weights of 350 and 750 were used. For each type of phosphonate, a series of polymers were prepared with pendent group concentrations ranging from 0 to 9.1 substituents per 100 carbon atoms. The modified polymers were characterized by infrared spectroscopy, differential scanning calorimetry, and by measurement of the tensile modulus. Infrared spectroscopy proved to be useful for determining if the polymer modification reaction resulted in entirely phosphonate ester pendent group substitutions or if unesterified phosphonic acid groups were also present. The polymers prepared in this investigation exhibited no infrared absorbances arising from phosphonic acid groups. The presence of phosphonate ester groups resulted in a decrease of crystallinity with increasing phosphonate concentration and with the exception of the polymers containing 9.1 PEO–phosphonate grafts per 100 carbon atoms, the effect of phosphonylation on the melting temperature of the polymers was consistent with Flory's theory for the melting point depression of random copolymers. The tensile modulus measured from a constant uniaxial elongation experiment decreased with increasing phosphonylation. The behavior of all three phosphonate series was identical and could be attributed to the effect of decreasing polymer crystallinity.     

Diastereoselective synthesis of 2-amino-4-phosphonobutanoic acids by electrophilic substitution and tin-Peterson olefination of bis-lactim ethers derived from cyclo-[L-AP4-D-Val

Electrophilic substitutions on lithiated Sch?llkopf's bis-lactim ethers derived from cyclo-[L-AP4-D-Val] take place regio- and stereoselectively at the alpha-position of the phosphonate ester. Subsequent olefination of alpha-silyl-, alpha-phosphoryl-, and alpha-stannyl-stabilized phosphonate carbanions give rise exclusively to vinylphosphonates. Both processes allow a direct and stereoselective access to a variety of 4-substituted and 3,4-disubstituted 2-amino-4-phosphonobutanoic acids (AP4 derivatives) in enantiomerically pure form that may be useful tools for characterizing the molecular pharmacology of metabotropic glutamate receptors (mGluRs) of group III. The relative stereochemistry was assigned from X-ray diffraction analyses or NMR studies of 1,2-oxaphosphorinane and other cyclic derivatives. In accordance to density functional theory (DFT) calculations, the syn-selectivity in the electrophilic substitutions may originate from the intervention of seven- and eight-membered chelate structures in which the bis-lactim ether moiety shields one of the faces of the phosphonate carbanion. DFT calculations for the tin-Peterson olefination of alpha-stannyl stabilized phosphonate carbanions indicate that rate and selectivity are determined in the initial carbon-carbon bond formation step where the unlike transition structures leading to (Z)-vinylphosphonates are favored both in the gas phase and in THF solution.