Copper-Catalyzed Desaturation of Lactones, Lactams, and Ketones under pH-Neutral Conditions
作者:Ming Chen、Guangbin Dong
DOI:10.1021/jacs.9b07932
日期:2019.9.18
A copper-catalyzed desaturation method is reported, which is suitable for converting lactones, lactams and cyclic ketones to their α,β-unsaturated counterparts. The reaction does not require strong base/acid or sulfur/selenium reagents, and can be carried out through a simple one-step operation. The protocol uses inexpensive catalysts and reagents, exhibits excellent scalability and functional group
报道了一种铜催化的去饱和方法,该方法适用于将内酯、内酰胺和环酮转化为它们的 α,β-不饱和对应物。该反应不需要强碱/酸或硫/硒试剂,可通过简单的一步操作进行。该协议使用廉价的催化剂和试剂,具有出色的可扩展性和官能团耐受性。值得注意的是,叔丁醇是唯一产生的化学计量副产物,并且没有观察到过度氧化。通过对照实验、氘标记、自由基钟、EPR、HRMS 和动力学研究研究了反应机理。获得的数据与涉及可逆α-去质子化的反应途径一致,Cu(II)-OtBu 物种,然后进一步氧化所得的 Cu 烯醇化物。
A simple strategy for spirocyclopentannulation of cyclic ketones. Formal total synthesis of (±)-acorone
A general and simple methodology for spirocyclopentannulation of cyclic ketones (or 4,4-disubstituted cyclopentenones from acyclic ketones) and its application in the synthesis of the spirodienone via a prochiral precursor constituting a formal totalsynthesis of (±)-acorone (), are described.
Platinum‐Catalyzed α,β‐Desaturation of Cyclic Ketones through Direct Metal–Enolate Formation
作者:Ming Chen、Guangbin Dong
DOI:10.1002/anie.202013628
日期:2021.3.29
ketones to their conjugated α,β‐unsaturated counterparts is reported in this full article. A unique diene‐platinum complex was identified to be an efficient catalyst, which enables direct metal‐enolate formation. The reaction operates under mild conditions without using strong bases or acids. Good to excellent yields can be achieved for diverse and complex scaffolds. A wide range of functional groups, including
Mechanistic and exploratory organic photochemistry. LXXXVII. Photochemical rearrangement of 4-aryl-substituted cyclopentenones. Low-temperature photochemistry and direct observation of reaction intermediates