4970-78-9Relevant academic research and scientific papers
Visible-Light-Induced in Situ Generation of Fischer-Type Copper Carbene Complexes from Acylsilanes and Its Application to Catalytic [4 + 1] Cycloaddition with Siloxydienes
Takeuchi, Taiichi,Aoyama, Tsukasa,Orihara, Kurumi,Ishida, Kento,Kusama, Hiroyuki
, p. 9490 - 9494 (2021/12/14)
A novel methodology for in situ generation of Fischer-type metal–carbene complexes was developed. Photoirradiation to a mixture of an acylsilane and a cationic copper complex cleanly gave a Fischer-type copper–siloxycarbene complex, which was detected by spectroscopic methods. This carbene complex reacted with siloxydienes in a [4 + 1] cycloaddition manner to give cyclopentene derivatives. It is noteworthy that this reaction proceeds with a catalytic amount of copper through in situ generation of a Fischer-type copper–siloxycarbene complex intermediate.
Enantioselective Synthesis of γ-Functionalized Cyclopentenones and δ-Functionalized Cycloheptenones Utilizing a Redox-Relay Heck Strategy
Yuan, Qianjia,Prater, Matthew B.,Sigman, Matthew S.
, p. 326 - 330 (2019/11/14)
In this report, the desymmetrization of cyclic enones under relay Heck conditions with an array of aryl boronic acids, alkenyl triflates and indole derivatives is described. This method grants facile access to diverse γ-functionalized cyclopentenones and δ-functionalized cycloheptenones. Using this approach, a formal synthesis of (S)-baclofen was completed in high yield and excellent enantioselectivity. (Figure presented.).
Regio- and stereoselective synthesis of cyclopentenones: Intermolecular Pseudo-Pauson-Khand cyclization
Barluenga, Jose,Alvarez-Fernandez, Ana,Suarez-Sobrino, Angel L.,Tomas, Miguel
supporting information; experimental part, p. 183 - 186 (2012/03/26)
Doing the two step: A very simple two-step access to polysubstituted cyclopentenones from terminal alkynes, [M(CO)6], and bromoalkenes is described. This protocol is an alternative to the intermolecular Pauson-Khand reaction, and can be used wi
Polymer-mediated reactions. A Nazarov-like cyclization
Pavlik, Christopher,Morton, Martha D.,Invernale, Michael A.,Berghorn, Ian D.,Sotzing, Gregory A.,Smith, Michael B.
supporting information; experimental part, p. 2195 - 2199 (2011/11/06)
The polymer PEDOT+ mediates a Nazarov-like cyclization of dienones, in an heterogeneous system and in hydrocarbon solvents. The polymer-mediated reactions show clear differences in product formation when compared to the same reaction with tosic acid, or when compared to reports in the literature. Comparable or improved yields are observed, as well as the ability to give a -Nazarov product in cases where treatment with acid fails to give cyclization, or leads to an undesirable rearrangement. In addition, the ability to recycle the polymer makes this a potentially useful protocol for an important organic chemical reaction. Georg Thieme Verlag Stuttgart · New York.
Reaction of Alkynes with Cyclopropylcarbene-Chromium Complexes: A Versatile Cycloaddition Reaction for the Construction of Cyclopentenones
Tumer, Seniz U.,Herndon, James W.,McMullen, Leonard A.
, p. 8394 - 8404 (2007/10/02)
The scope and limitations of the reaction between cyclopropylcarbene-chromium complexes and alkynes have been examined.A variety of cyclopropylcarbene complexes and alkynes have been employed in these studies.The reaction appears to be general for most simple alkynes, producing cyclopentenones.A mechanism has been proposed involving metallacyclobutene formation, electrocyclic ring opening, electrocyclic ring closure, CO insertion, alkene insertion, metallacyclopentene fragmentation and cyclopentadienone reduction.The presence of these intermediates has been inferred from the structure of products obtained when the reaction was conducted in acetonitrile instead of dioxane.A trapping experiment employing 1,6-heptadiyne supports the intermediacy of vinylcarbene or vinylketene complexes.
