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   36篇
  免费   1篇
化学   31篇
力学   1篇
数学   4篇
物理学   1篇
  2021年   1篇
  2019年   1篇
  2018年   4篇
  2017年   1篇
  2016年   1篇
  2014年   1篇
  2013年   3篇
  2012年   2篇
  2011年   6篇
  2010年   3篇
  2009年   3篇
  2008年   3篇
  2007年   4篇
  2006年   2篇
  2005年   1篇
  2004年   1篇
排序方式: 共有37条查询结果,搜索用时 15 毫秒
21.
(?)-α-Conhydrine was synthesized from propargyl alcohol in 20% overall yield in nine steps. The key intermediates were obtained via a regioselective epoxide opening, cross-metathesis, tandem hydrogenation and hydrogenolysis, and stereoselective dihydroxylaton. The side product from the epoxide ring opening was used to synthesize the seven-membered amino sugar DMJ analogue.  相似文献   
22.
23.
The preparation of 2-(arylmethoxy)isopinocampheols from pinanediol via the DIABL-H reduction of the corresponding aryl aldehyde acetals has been described. A systematic examination of the asymmetric aldol reaction of 3,3,3-trifluoropropionates led to the double diastereoselective aldol reaction of 2-(arylmethoxy)isopinocampheyl 3,3,3-trifluoropropionates providing anti-α-trifluoromethyl-β-hydroxy esters in 63-85% yields, ?99% anti-selectivity and 80-96% de for the anti-isomer.  相似文献   
24.
We have introduced and studied a new class of fuzzy irresolute functions, called fuzzy strongly pre-irresolute functions, by using fuzzy preopen sets.  相似文献   
25.
Journal of Thermal Analysis and Calorimetry - In the present paper, we reported the accurately measured densities (ρ), speed of sound (u) and refractive index (nD) for the binary mixture of...  相似文献   
26.
The aim of this paper is to give a new class of fuzzy open sets called fuzzy pre-γ-open sets in fuzzy topological spaces. Also,a new type of fuzzy continuous functions called,fuzzy pre-γ-continuous functions is introduced and studied.  相似文献   
27.
A facile synthetic method of 3,4-disubstituted 2,5-dihydrofurans and 2,5-dihydropyrroles starting from the Baylis-Hillman adducts was developed. The 2,5-dihydrofuran skeleton was constructed via the consecutive radical cyclization, hydrolysis, halolactonization, and spontaneous decarboxylation strategy starting from the modified Baylis-Hillman adducts.  相似文献   
28.
Novel pentacyclic benzoazepino[2,1-a]isoindole derivatives were synthesized by palladium-mediated consecutive cyclization from enamides of Baylis-Hillman adducts.  相似文献   
29.
Construction of furo[3,4-c]pyran ring skeleton was achieved starting from the Baylis-Hillman adducts. The synthesis was carried out by the successive introduction of propargyl alcohol, radical cyclization, reduction, allylation, and finally ring-closing metathesis reaction.  相似文献   
30.
Synthesis of dihydronaphthalene derivatives was carried out by allyltributylstannane-mediated vinyl radical cyclization as the key step from 4-aryl-1-iodobutene derivatives, which were derived from Baylis-Hillman adducts via vinyl radical cyclization.  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