Expedient Access to 2,3-Dihydropyridines from Unsaturated Oximes by Rh(III)-Catalyzed C–H Activation
摘要:
alpha,beta-Unsaturated - oxime pivalates are proposed to undergo reversible C(sp(2))-H insertion with cationic Rh (III) complexes to furnish five-membered metallacycles. In the presence of 1,1-disubstituted olefins, these species participate in irreversible migratory insertion to give, after reductive elimination, 2,3-dihydropyridine products in good yields. Catalytic hydrogenation can then be used to. convert these molecules into piperidines, which are important structural components of numerous pharmaceuticals.
New Metal-Free One-Pot Synthesis of Substituted Allenes from Enones
作者:Meng Tang、Chun-An Fan、Fu-Min Zhang、Yong-Qiang Tu、Wen-Xue Zhang、Ai-Xia Wang
DOI:10.1021/ol802445p
日期:2008.12.18
A new metal-free, one-pot synthesis of substituted allenes from enones was discovered for the first time, in which a tertiary amine as a base was found to be an effective promoter in such novel transformations. The present synthetic protocol proceeded readily with high compatibility of sensitive functional groups, and it provides a new efficient way to access a series of synthetically important allenes
Stability, Reactivity, Solution, and Solid-State Structure of Halomethylzinc Alkoxides
作者:André B. Charette、Carmela Molinaro、Christian Brochu
DOI:10.1021/ja010837+
日期:2001.12.1
regarding the development of a Lewis acid-catalyzed cyclopropanation of allylic alcohols with bis(iodomethyl)zinc. Iodomethylzinc alkoxides can be formed by treatment of an alcohol with bis(iodomethyl)zinc. These species are not prone to undergo cyclopropanation at low temperature but the addition of a Lewisacid in catalytic amounts induces the cyclopropanationreaction. Using this procedure, we demonstrated
A Carbohydrate-Based Approach for the Total Synthesis of 1,3-Polyol/α-Pyrone Antifungal Natural Products
作者:C. V. Ramana、Burgula Srinivas、Vedavati G. Puranik、Mukund K. Gurjar
DOI:10.1021/jo050972v
日期:2005.9.1
α-d-glucoheptonic-γ-lactone derivative has been applied to prepare a differentially protected anti,anti-1,3,5-triol system, the utility of which has been extended for the total synthesis of anti-fungal 1,3-polyol/α-pyronenatural products.
Development of novel tail-modified anandamide analogs
作者:Fenmei Yao、Chen Li、Subramanian K. Vadivel、Anna L. Bowman、Alexandros Makriyannis
DOI:10.1016/j.bmcl.2008.07.110
日期:2008.11
To explore the hydrophobic groove subsite within the CB1 cannabinoid receptor we have designed and synthesized a group of tail-substituted anandamide analogs. Our design involves the introduction of aryl or heterocyclic ring as terminal substituents that are connected to the last cis-arachidonyl double bond through aliphatic chains of variable lengths. Our results indicate that there are strict stereochemical requirements for the interaction of such analogs with the CB1 receptor. The optimal pharmacophore includes the phenyl, p-substituted phenyl, or 3-furyl substituents attached to the cis-double bond through a four methylene chain. Published by Elsevier Ltd.
Expedient Access to 2,3-Dihydropyridines from Unsaturated Oximes by Rh(III)-Catalyzed C–H Activation
作者:Fedor Romanov-Michailidis、Kassandra F. Sedillo、Jamie M. Neely、Tomislav Rovis
DOI:10.1021/jacs.5b04946
日期:2015.7.22
alpha,beta-Unsaturated - oxime pivalates are proposed to undergo reversible C(sp(2))-H insertion with cationic Rh (III) complexes to furnish five-membered metallacycles. In the presence of 1,1-disubstituted olefins, these species participate in irreversible migratory insertion to give, after reductive elimination, 2,3-dihydropyridine products in good yields. Catalytic hydrogenation can then be used to. convert these molecules into piperidines, which are important structural components of numerous pharmaceuticals.