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Homochiral cis,cis-; cis,trans- and trans,trans-spiro[4.4]nonane-1,6-diols were prepared via diastereoselective reduction of enantiomerically pure spiro[4.4]nonane-1,6-dione (1) with the corresponding reducing agents: lithium n-butyldiisobutylaluminium hydride for cis,cis-diol (2) with 88% yield; BH3·THF for cis, trans-diol (3) with 91% yield; LiAlH4 for trans,trans-diol (4) with 15% yield. 相似文献
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Chiral diphosphite ligands were prepared by the reaction of (1R,5S,6R)-(trans, trans)-spiro[4.4]nonane-1,6-diol with chlorophosphites. The rhodium(Ⅰ) complexes containing these ligands were tested in the asymmetric hydroformylation of styrene and moderate enantioselectivity (up to 49% ee) was obtained. A pair of diastereomers 5a and 5b gave the opposite configuration of the product, which implies that the sense of enantioface selection is mainly dictated by the configuration of the terminal group on the ligand. 相似文献
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在优良抗风湿药物萘普生的重要中间体6-甲氧基-2-乙酰素的合成中存在溶剂硝基苯的毒性及所带来的污染。而改用二氯乙烷作溶剂,只加少量硝基苯即可。为配合合成工艺的优化,用气相色谱(GC)、气相色谱-质谱(GC/MS)对反应产物、副产物及多个杂质进行了定性分析研究,并在5%OV-101ChromosorbWAWDMCS柱上完成了产物的内标定量分析。从而减少了副反应和高沸点杂质的生成,最终生产出了95%以上含量的6-甲氧基-2-乙酰萘产品,收率达到60%。 相似文献
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From (+)- camphor, six new (+)-camphor derivatives were synthesized. According tothe structure and chemical properties of the derivatives, the relation between the substitutedgroups and the stereoselectivity of alkylations and reduction was examined. It is found thatthe chemical shift of protons of C(8), C(9) methyl groups and chemical properties of carbonylO(2) are associated with the substituted groups. 相似文献
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二唑衍生物具有抗菌、消炎和调节植物生长等活性[1~5].二唑硫醚衍生物也具有一定抗菌活性[6].为筛选具有生物活性的新化合物和研究亲核取代反应的规律,我们设计和合成了新的2-酰肼基-5-(2,4-二氯苯基)-1,3,4-二唑2,研究了2在K2C... 相似文献