Deprotection of benzyl and p-methoxybenzyl ethers by chlorosulfonyl isocyanate–sodium hydroxide
摘要:
CSI-NaOH procedure provided a new and mild methodology for the deprotection of benzyl and p-methoxybenzyl ethers without affecting the other functional groups under similar reaction conditions. (C) 2003 Elsevier Science Ltd. All rights reserved.
The specification generally relates to compounds of Formula (I):
and pharmaceutically acceptable salts and prodrugs thereof, where R
1
, R
4
, R
5
, R
6
, R
7
, Linker, X, Y, A, G, D and E have any of the meanings defined herein. This specification also relates to the use of such compounds and pharmaceutically acceptable salts and prodrugs thereof in methods of treatment of the human or animal body, for example in prevention or treatment of cancer. This specification also relates to processes and intermediate compounds involved in the preparation of such compounds and to pharmaceutical compositions containing them.
Medium-Sized Heterocycle Synthesis by the Use of Synergistic Effects of Ni-NHC and γ-Coordination in Cycloisomerization
作者:Chun-Yu Ho、Lisi He
DOI:10.1021/jo5008477
日期:2014.12.19
an NHC–NiH catalyst and γ-heteroatom chelation were used together as a basis for 1,n-diene termini differentiation and for nγ-exo-trig (head-to-tail) product selectivity. Heterocycles bearing an exocyclic methylene such as oxepines, thiepines, siloxepines, and oxocanes were synthesized from the corresponding 1,n-dienes by a fine-tuning of the NHC properties. The implication of the underlying hypothesis
Low Catalyst Loading in Ring-Closing Metathesis Reactions
作者:Renat Kadyrov
DOI:10.1002/chem.201202207
日期:2013.1.14
conversion into a broad variety of 5–16‐membered heterocyclic compounds. The practicality of this procedure was illustrated in the synthesis of 5–8‐membered N‐tert‐butoxycarbonyl (N‐Boc)‐ and N‐para‐toluenesulfonyl (N‐Ts)‐protected cyclic amines and 9–16‐membered lactones. The synthesis of macrocyclic proline‐based lactams required slightly higher catalyst loadings. Along with monocyclic products, oligomeric
描述了一种有效的闭环复分解反应程序。在几分钟内可以达到95%的二烯丙基丙二酸二乙酯在稀溶液中的转化率,达到TOF = 4173 min -1,而载有不饱和NHC配体的商业化Ru催化剂的负载量却非常低。通常,仅需50至250 ppm的催化剂即可将近定量转化为多种5-16元杂环化合物。此过程的实用性在5-8元的合成图示ñ -叔丁氧羰基(Ñ -Boc) -和ñ -对甲苯磺酰(Ñ-Ts)保护的环胺和9-16元内酯。大环脯氨酸基内酰胺的合成需要稍高的催化剂负载量。与单环产物一起,分离并表征了寡聚副产物,主要是环二聚体。
Lewis Acid Assisted Ruthenium-Catalyzed Metathesis Reactions
The combination of a ruthenium–arene complex, a noncoordinating salt, and a Lewisacid facilitates access to a highlyactive and selective in situ metathesiscatalyst. The catalyst is formed from an inexpensive ruthenium precursor and olefins are used as the substrates. RCM=Ring‐closing metathesis, acac=acetylacetonate.
APPARATUS AND METHOD FOR CARRYING OUT MULTIPLE REACTIONS
申请人:Bowden Ned
公开号:US20090299102A1
公开(公告)日:2009-12-03
The invention provides methods and an apparatus useful for site-isolating reagents or catalysts during chemical reactions. The methods and apparatus are useful for carrying out cascade or domino reactions.