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聚乙醇酸及其与乳酸的共聚物是一类无毒、有良好的生物相容性和生物可降解材料,它们广泛地用作药物控释体系的载体,牙科植入材料[1,2].但由于聚乙醇酸的高度可结晶性,使其不溶于包括三氟乙酸在内的几乎所有的有机溶剂,因此通过共聚来改进其物化性质的研究一直方...  相似文献   

3.
报道了trans-2-氧代-2-氯-4-苯基-5,5-二甲基-1,3,2-二氧磷杂环己烷以及cis-2-硫代-2-氯-4-苯基-5,5-二甲基-1,3,2-二氧磷杂环己烷甲醇解反应的立体化学。结果表明,反应体系的酸碱性对前者甲醇解反应的立体化学有着重要影响。而硫代环磷酰氯在碱性条件下的甲醇解反应存在一个开环异构化过程。  相似文献   

4.
报道了trans-2-氧代-2-氯-4-苯基-5,5-二甲基-1,3,2-二氧磷杂环己烷以及cis-2-硫代-2-氯-4-苯基-5,5-二甲基-1,3,2-二氧磷杂环己烷甲醇解反应的立体化学。结果表明,反应体系的酸碱性对前者甲醇解反应的立体化学有着重要影响。而硫代环磷酰氯在碱性条件下的甲醇解反应存在一个开环异构化过程。  相似文献   

5.
通过相转移催化关环反应合成了新的6-取代-2-疏-2-烷(芳)氧-4-(2,-4二氯苯基)-4-氢-1,3,2-苯并二氧磷杂环已烷(3a-3g),用结晶法分离得到7对非对联消旋体,其结构经1HNMR、31PNMR和元素分析确证,化合物3a-A单晶X射线分析表明其构型为(2R,4S;2S,4R).生物活性测定结果表明,化合物3C有良好的杀虫活性,非对映消旋体A和B具有协同杀虫作用.  相似文献   

6.
以苯甲醛、异丁醛、三氯化磷为原料合成了新型的1,3,2-二氧磷杂环类化合物2-苯羟甲基-5,5-二甲基-4-苯基-2-氧代-1,3,2-二氧磷杂环己烷,总收率为40.8%,并对其进行了NMR研究和结构表征。  相似文献   

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通过相转移催化关环反应合成了新的6-取代-2-硫-2-烷(芳)氧-4(2,4-二氯苯基)-4-氢-1,3,2-苯并二氧磷杂环己烷(3a-3g),用结晶法分离得到了7对非对映消旋体,其结构经HNMR、^31PNMR和元素分析确证,化合物3a-A单晶X射线分析表明其构型为(2R,4S;2S,4R),生物活性测定结果表明,化合物3c有良好的杀虫活性,非对映消旋体A和B具有协同杀虫作用。  相似文献   

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本文合成29个新的苯并二氧磷杂戊环化合物,探索了适宜的反应条件及产物的提纯方法.通过UV、IR、Raman、NMR和MS对所有化合物的结构进行了初步的解析.高分辨质谱数据表明P=S双键的硫原子与磷杂戊环上芳基氧原子在质谱中发生硫逐-硫赶异构化。  相似文献   

11.
In the presence of pyridine, the Pd-catalyzed addition reaction of CO and CCI4 to 1-octene could be carried out smoothly under mild conditions. In this reaction, the satisfactory results were afforded when different alcohols and palladium catalysts were used.  相似文献   

12.
1H NMR-spectroscopic investigations of the acid catalyzed addition of methanol to dihydrodipyrrinones (Z)-2, (E)-2, and4 show the C-protonation of their enamide parts to be the first and rate determining step forming the key intermediate, the N-acyl-immonium ion N+. Its ability to add nucleophiles diastereoselectively can be used to prepare the adductsl-3 andl-5. Exclusive formation of thelike-isomer can be explained by a stereoelectronically favoured approach of the nucleophile and by the thermodynamically favoured arrangement of the bulky ring substituents. Both explanations are based on low temperature X-ray crystal structure determinations: in the first place, the orientation of the added nucleophile could be found to be nearly parallel to the -plane of the lactam unit and quasi-axial with respect to theenvelope-like conformation of the five-ring lactam; in the second place, the relative orientation of the methoxycarbonyl-metyl-group at C-3 and the pyrrolylmethyl-substituent at C-4 could be found to be atrans-quasi-diequatorial one.
  相似文献   

13.
Microwave-assisted reaction of dimethyl H-phosphonate with cyclohexene-, 1,2-butene-, and 1,2-decene oxides furnishes 8, 5, and 17 compounds, respectively. The probable mechanism of the formation of the various compounds via free radical reactions and their GC-MS characterization are presented in this article.  相似文献   

14.
3-Benzoylquinoxalin-2(1H)-one is cyclized with acetic anhydride in the presence of pyridine into 2-oxo-4-phenylpyrano[2,3-b]quinoxaline.  相似文献   

15.
IntroductionInpreviouspaper[1—3],wedescribedthatarenealdoximedehydrodimerandstyreneinre-fluxingchloroformgavelinearadductsand...  相似文献   

16.
胡扬根  徐靖  陈小保  屈永年 《有机化学》2009,29(11):1853-1857
应用膦亚胺3与芳基异氰酸酯的氮杂Wittig反应, 生成碳二亚胺4, 4再分别与酚、醇作用, 在碳酸钾或醇钠催化下关环, 以72%~88%的产率合成了2-烷(芳)氧基取代-苯并呋喃并[3,2-d]嘧啶-4(3H)-酮衍生物5和6, 其结构经IR, 1H NMR, MS和元素分析证实. 初步生物活性测试表明该类化合物表现出温和的杀菌活性. 如5f在50 mg/L浓度时, 对黄瓜灰霉菌的抑制率为55%.  相似文献   

17.
O—芳基苯基硫代膦酰肼与异(硫)氰酸酯的加成反应   总被引:2,自引:0,他引:2  
合成了一些新的硫代膦酰基-及N,N′-双(硫代膦酰基)氨基硫脲。分离并采用IR、~1H NMR、MS及X衍射确证了N,N′-双[硫代膦酰基]氨基硫脲中是由2个手性磷原子而形成的非对映异构体。讨论了单取代和双取代氨基硫脲的质谱。  相似文献   

18.
The hitherto unreported title compounds were obtained in good yields by the application of [3,3]sigmatropic rearrangement on 4-]2′-propynyloxy] [1]benzothiapyran-2-one and 4-[2′-propenyloxy][1]benzothiapyran-2-one or 4-[2′-chloro-2′-propenyloxy][1]benzothiapyran-2-one respectively.  相似文献   

19.
用Heck反应合成1-羟基-4-(3-吡啶基)丁-2-酮   总被引:1,自引:0,他引:1  
蔡春  吕春绪 《有机化学》2004,24(6):673-674
在Heck反应条件下,以Ph3P为催化剂配体,由3-卤代吡啶和3-丁烯-1,2-二醇进行偶合可以得到1-羟基-4-(3-吡啶基)丁-2-酮,具有原料易得、合成方法简单的优点.  相似文献   

20.
The title compound (C16H14BrNO) has been synthesized by the reaction of p-tolylamine, Meldrum’s acid and 4-bromo-benzaldehyde, and its structure was characterized by IR, 1H NMR and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with a = 7.6850(11), b = 8.3004(11), c = 21.301(3) , β = 95.110(2)°, V = 1353.4(3) 3, Mr = 316.19, Z = 4, Dc = 1.552 g/cm3, μ(MoKα) = 3.028 mm-1, F(000) = 640, the final R = 0.0345 and wR = 0.0768. X-ray analysis reveals that the atoms of C(1), C(2), C(3), C(4), C(5) and N(1) form a six-membered ring of boat conformation.  相似文献   

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