首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   75篇
  免费   4篇
  国内免费   4篇
化学   81篇
物理学   2篇
  2021年   2篇
  2020年   5篇
  2019年   3篇
  2018年   2篇
  2017年   4篇
  2016年   5篇
  2015年   6篇
  2014年   10篇
  2013年   21篇
  2012年   5篇
  2011年   8篇
  2010年   6篇
  2009年   3篇
  2006年   1篇
  2001年   2篇
排序方式: 共有83条查询结果,搜索用时 15 毫秒
81.
Aromatic amine phosphonato esters 4a–d were obtained in excellent yields from the 1:1:1 addition reaction between triphenyl phosphite and dimethyl acetylenedicarboxylate in the presence of NH‐aromatic amines such as 2‐aminobenzophenone, 2‐aminoacetophenon, methyl‐2‐aminobenzoate, and 2‐aminobenzonitrile. In the recent works, the assignments of the configuration of 4a–d corresponding to the three‐bond carbon‐phosphorus coupling, 3Jpc, was determined on the basis of coupling constants by the Karplus equation as 2R *, 3R *or 2S *, 3S * while they were 2R *, 3S * or 2S *, 3R * in our previous works in the presence of same solvent. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:240–245, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20541  相似文献   
82.
A novel one‐pot three‐component condensation reaction of an aldehyde, 2‐aminopyrimidine and 2‐naphthol to afford the corresponding 2‐aminopyrimidinomethylnaphtols in good yields. The remarkable features of this new procedure are high conversions, short reaction time, clean reaction profiles, and environmentally benign and simple work‐up procedures.  相似文献   
83.
Stable crystalline phosphorus ylides containing chlorine and sulfur were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylene-dicarboxylates in the presence of 6-chloro-2-benzoxazolethiol and 2-chloro-phenothiazine. These stable ylides exist in solution as a mixture of two geometrical isomers. This is caused by the conjugation of the ylide moiety with the adjacent carbonyl group, which results in a restricted rotation around the respective carbon-carbon bond.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号