Synthesis of ferroelectric liquid crystalline polysiloxanes containing (S)-2-methylbutyl 4-alkyloxybiphenyl-4′-carboxylate and (2S, 3S)-2-chloro-3-methylpentyl 4-alkyloxybiphenyl-4′-carboxylate

The synthesis of side-chain liquid crystalline polysiloxanes containing (S)-2-methylbutyl-4-alkyloxybiphenyl and (2S, 3S)-2-chloro-3-methylpentyl 4-alkyloxybiphenyl-4-carboxylate moieties as mesogenic units and aliphatic spacers containing respectively three to eleven methylene units is presented. Differential scanning calorimetry, optical polarizing microscopy and X-ray diffraction measurements reveal chiral smectic mesomorphism for most of the obtained polymers. Two polysiloxanes that contain respectively three methylene units in their spacers exhibit an enantiotropic smectic A phase or no mesophase. Four polysiloxanes that contain respectively five, six and eleven methylene units in their spacers exhibit enantiotropic smectic A and chiral smectic C phases. The results seem to demonstrate that the tendency toward chiral smectic C mesomorphism increases with increasing spacer length. Incorporation of a chloro-containing chiral end group into the mesogenic core of a polymer will decrease the thermal stability of the mesophase formed.     

Synthesis and mesomorphic behavior of poly[(2S, 3S)-(+)-2-chloro-3-methylpentyl 4′-(ω-vinyloxyalkyloxy)biphenyl-4-carboxylate]s with ethyl and propyl alkyl groups

Summary The synthesis and cationic polymerization of (2S, 3S)-(+)-2-chloro-3-methylpentyl 4-(2-vinyloxyethyloxy)biphenyl-4-carboxylate (15–2) and (2S, 3S)-(+)-2-chloro-3-methylpentyl 4-(3-vinyloxypropyloxy)biphenyl-4-carboxylate (15–3) are described. The mesomorphic behavior of the resulting polymers is discussed as a function of the molecular weight and spacer length. Based on the second and subsequent heating and cooling scans, poly(15–2)s exhibit an enantiotropic S_X (unidentified smectic) phase. Poly(15–2) with DP=4 is only crystalline. Poly(15–3)s show an enantiotropic cholesteric phase and an inverse monotropic S_X phase.     

(S)-4-(甲硫基)-2-[2-羰基-1-吡咯烷基]丁酰胺的合成

(S) 2 氨基 4 (甲硫基)丁酸甲酯盐酸盐于浓氨水中,发生酰胺化反应,制得(S) 2 氨基 4 (甲硫基)丁酰胺,收率63%;(S) 2 氨基 4 (甲硫基)丁酰胺用甲醇溶解,与浓盐酸成盐,得(S) 2 氨基 4 (甲硫基)丁酰胺盐酸盐,收率66%;(S) 2 氨基 4 (甲硫基)丁酰胺盐酸盐在相转移催化剂四丁基溴化铵(TBAB)及研细氢氧化钾的作用下,与4 氯丁酰氯发生取代、环化反应,制得(S) 4 (甲硫基) 2 [2 羰基 1 吡咯烷基]丁酰胺,收率61%。产品的结构经TLC、IR、1HNMR等进行了表征。     

(2S,4S)-4-羟脯氨酸的合成工艺研究

以(2S,4R)-4-羟脯氨酸为基础原料,以水为介质,利用三苯基膦和醇的Mitsunobu合成反应,改变其构型得到(2S,4S)-4-羟脯氨酸。此方法在现有合成路线基础上有所改进,在实验过程中探索反应物配比对各步反应收率的影响,得到实验的最优条件。并对产物进行表征及纯度分析,确定为(2S,4S)-4-羟脯氨酸,纯度为87.2%,收率93.3%。     

Synthesis and Thermotropic Studies of Two Novel Series of Kinked Liquid Crystals: 2-(4′-Alkoxybiphen-4-yl)-6-methylquinolines and 2-(6-Alkoxynaphthalen-2-yl)-6-methylquinolines

Two novel homologous series of kinked (Z-shaped) liquid crystalline compounds were synthesized using a short two-step reaction. Yields of 30%–40% and 51%–57% were obtained for 2-(4′-alkoxybiphen-4-yl)-6-methylquinolines (nO-PPQMe, n = 3–8) and 2-(6-alkoxynaphthalen-2-yl)-6-methylquinolines (iO-NpQMe, i = 3–7), respectively. Spectral analyses agreed with the expected structures. The thermotropic behaviors of these compounds were investigated using polarized optical microscopy and differential scanning calorimetry. An enantiotropic nematic phase appeared to be the main mesophase in these two series of kinked liquid crystalline compounds, and an additional enantiotropic smectic C phase appeared when n = 8.     

(5R,6S)-2-(4-甲氧基)苯基-6-[(1R)-叔丁基二甲基硅氧乙基]-青霉烯-3-羧酸乙酯的合成

以(3R,4R)-3-[(1R)-叔丁基二甲基硅氧乙基]-乙酰氧基氮杂环丁-2-酮(4AA)为原料,经取代、酰化、Wittig反应,合成了标题化合物,化合物结构经 1HNMR、IR、元素分析和质谱表征.     

(S)-4-(2-甲基丁基)-4'-(4-丙基环己基)-2-氟联苯的合成及性能研究

以(S)-(2-甲基丁基)苯为原料,经碘代和Suzuki偶联四步反应,合成了手性液晶(S)-4-(2-甲基丁基)-4'-(4-丙基环己基)-2-氟联苯,总收率11.4%,纯度99.2%,并采用IR、MS、1H NMR及元素分析对其结构进行了表征。结合差示扫描量热仪(DSC)和偏光显微镜(POM)研究了目标化合物的介晶性,并采用Cano’s wedge法测定了目标化合物的扭曲力。     

(R)-2-[4-(6-氯-2-苯并噁唑氧基)苯氧基]丙酸的合成研究

以(R)-2-(4-羟基苯氧基)丙酸和2,6-二氯苯并噁唑为原料,在碱性条件下反应合成除草剂中间体(R)-2-[4-(6-氯-2-苯并噁唑氧基)苯氧基]丙酸。研究了反应时间、反应温度、物料比及催化剂对反应的影响。该法具有反应条件温和,收率高及适宜于工业化等优点。     

(1S,4S)-2-甲基-2,5-二氮杂二环[2.2.1]庚烷的合成

以N—位磺酰化的反—4—羟基—L—脯氨酸为原料,以硼氢化钾与氯化锌还原羧基,以三乙胺和丙酮代替吡啶进行羟基磺酰化和羟基氯代反应,“一锅煮”进行取代环合和去N—磺酰化合成(1S,4S)—2—甲基—2,5—二氮杂二环[2．2．1]庚烷,总收率达53％。该法操作简便,收率高,更有利于工业化生产。     

4-(S)-异丁基-2-吡咯烷酮的合成

以普瑞巴林为起始原料,经酰化、酯化、环合等一系列反应合成了4-(S)-异丁基-2-吡咯烷酮,收率93.8%,产物的结构经~1HNMR、~(13)CNMR、MS得到确证。     

(2S,4S)-1-(4-硝基苄氧羰基)-2-[(3-烯丙氧羰基)-苯基氨基甲酰基]-吡咯烷-4-基硫醇的合成工艺改进

采用价格低廉的反-4-羟基-L-脯氨酸为原料,通过7步反应,制备尔他培南的关键中间体———标题化合物,总收率37%。原料来源方便,成本低,而且减少了毒害作用,增加了安全性,适宜于工业化生产。     

(4S,5S)-4,5-双(对甲苯磺酸酯甲基)-2-(6-氯)正己基-1,3-二氧戊环的合成

以光活性Ｌｇ－（＋）－酒石酸为原料合成了尚未见文献报道的含Ｃ２对称轴的（４Ｓ,５Ｓ）－４,５－双（对甲苯磺酸酯甲基）－２－（６－氯）正己基－１,３－二氧戊环。对它进行了元素分析、氢核磁共振谱、碳核磁共振谱表征。     

2-[4-[2-[4-[1-(2-乙氧基)苯并咪唑-2-基]哌啶-1-基]乙基]苯基]-2-甲基丙酸的合成

以4-(2-溴乙酰基)-α,α-二甲基苯乙酸乙酯(2)为起始原料,先在酸性还原体系中还原,得到亚甲基还原产物(3)再与2-(哌啶-4-烷基)-1H-苯并咪唑(4)在有机碱的作用下进行缩合,然后在无水条件下使用氢化钠拔氢后与氯代乙基乙基醚(6)缩合得到(7),最后,将酯基水解得到2-[4-[2-[4-[1-(2-乙氧基)苯并咪唑-2-基]哌啶-1-基]乙基]苯基]-2-甲基丙酸(比拉斯汀,1)。     

铜(Ⅱ)的高选择性显色试剂2-[2-(4-羟基-6-甲基嘧啶)偶氮]-1-萘酚

合成了2-[2-(4-羟基-6-甲基嘧啶)偶氮]-1-萘酚并研究了其在金属的分光光度测定中应用的可能性。它与铜、镍、钴、铁和钯的反应是灵敏的,其与铜(Ⅱ)的反应更灵敏。在40％(v/v)甲醇溶液中,其摩尔吸光系数为3.07×10~4l·mol~(-1)·cm~(-1)。     

Trans-methyl-3-(3-[2-oxo-4-(4-benzyloxyphenyl)-1-(4-fluorophenyl)-azetidinyl] propanoate的合成

以对羟基苯甲醛为原料,经三步反应合成Trans-methyl-3-(3-[2-oxo-4-(4-benzyloxyphenyl)-1-(4-fluorophenyl)-azetidinyl]propanoate中间体,总收率66.3%.     

(S)-1-苯基-2-(2-吡啶基)乙胺-(S)-苹果酸盐的制备

EP063387981报道(S)-1-苯基-2-(2-吡啶基)乙胺具有药用活性,也是有机中间体。其中(S)-1-苯基-2-(2-吡啶基)乙胺-(S)-苹果酸是NMDA受体拮抗物。     

2-[(4R,6S)-6-甲酰基-2,2-二甲基-1,3-二氧六环-4-基]乙酸叔丁酯的制造方法

正本发明涉及一种具有光学活性的2-[(4R,6S)-6-甲酰基-2,2-二甲基-1,3-二氧六环-4-基]乙酸叔丁酯的制造方法,所述2-[(4R,6S)-6-甲酰基-2,2-二甲基-1,3-二氧六环-4-基]乙酸叔丁酯是制造各种HMG-CoA还原酶抑制剂时的核心中间体。根据本发明的制造方法,可利用高分子载体TEM-     

Photochemical [2+2] cycloaddition of the olefinic double bonds in the supramolecular rectangle [Ru4(η6-p-cymene)4(μ-oxalato)2(μ-4,4′-bipyridylethylene)2]4+

Self-assembly of 4,4′-bipyridylethylene (bpe) bidentate connector with the dinuclear arene ruthenium clip [Ru₂(η⁶-p-cymene)₂(μ-oxalato)Cl₂] in the presence of silver triflate affords the cationic organometallic rectangle [Ru₄(η⁶-p-cymene)₄(μ-oxalato)₂(μ-bpe)₂]⁴⁺ ([1][CF₃SO₃]₄). Upon UV irradiation of a methanol solution of [1]⁴⁺, dimerisation of the olefinic double bonds of the two parallel bpe ligands occurs, thus giving rise to the [2+2] cycloaddition derivative [Ru₄(η⁶-p-cymene)₄(μ-oxalato)₂(μ-tpcb)]⁴⁺ ([2][CF₃SO₃]₄) (tpcb = tetrakis(4-pyridyl)cyclobutane). The [2+2] photodimerisation reaction was followed by ¹H NMR spectroscopy. Moreover, the molecular structure of these two systems was deduced by one-dimensional and two-dimensional NMR experiments (¹H, ¹³C, ROESY, COSY, HSQC). These data suggest the formation of only the rctt-tetrakis(4-pyridyl)cyclobutane isomer.     

惰性SiO2→活性[SiO4]4-(中)

4 原料中硅(SiO2)质成分在烧成中表现的匹配特性 了解了结晶SiO2和硅酸盐矿物Si-O结构体解聚出活性[SiO4]4的过程后,应进一步认识它们在烧成中的特性表现.