Palladium-catalyzed oxamidation of alkenes: A new approach to benzoxazolidines
作者:Niranjan Panda、Sushree Arpitabala Yadav
DOI:10.1016/j.tet.2018.02.012
日期:2018.3
A novel palladium catalyzed protocol for the synthesis of benzoxazolidine by the reaction sulfamidophenol and terminal alkene was developed. This oxamidation process is simple and does not require any ligand, base or inert atmosphere for the overall transformation. From control experiments, it is apparent that the cross-coupling reaction proceeds with initial formation of enesulfonamide which undergoes
Palladium-Catalyzed Asymmetric Aminohydroxylation of 1,3-Dienes
作者:Hong-Cheng Shen、Yu-Feng Wu、Ying Zhang、Lian-Feng Fan、Zhi-Yong Han、Liu-Zhu Gong
DOI:10.1002/anie.201712350
日期:2018.2.23
A PdII‐catalyzed asymmetricaminohydroxylation of 1,3‐dienes with N‐tosyl‐2‐aminophenols was developed by making use of a chiral pyridinebis(oxazoline) ligand. The highly regioselective reaction provides direct and efficient access to chiral 3,4‐dihydro‐2H‐1,4‐benzoxazines in high yield and enantioselectivity (up to 96:4 e.r.). The reaction employs readily available N‐tosyl‐2‐aminophenols as a unique
利用手性吡啶双(恶唑啉)配体开发了Pd II催化的1,3-二烯与N-甲苯磺酰基-2-氨基苯酚的不对称氨基羟基化反应。高度区域选择性反应可直接高效地获得手性3,4-二氢-2 H -1,4-苯并恶嗪,且产率高且对映选择性高(高达96:4 er)。该反应采用现成的N-甲苯磺酰基-2-氨基苯酚作为独特的氨基羟基化试剂,是已知不对称氨基羟基化方法的补充。
Solvent-Controlled Pd(II)-Catalyzed Aerobic Chemoselective Intermolecular 1,2-Aminooxygenation and 1,2-Oxyamination of Conjugated Dienes for the Synthesis of Functionalized 1,4-Benzoxazines
作者:Ke Wen、Zhengxing Wu、Banruo Huang、Zheng Ling、Ilya D. Gridnev、Wanbin Zhang
DOI:10.1021/acs.orglett.8b00352
日期:2018.3.16
Pd(II)-catalyzed intermolecular 1,2-aminooxygenation and 1,2-oxyamination of conjugateddienes have been developed. The chemoselective preparation of a variety of 2-functionalized and 3-functionalized 1,4-benzoxazine derivatives was accomplished via the adjustment of a coordinating solvent. Oxygen was successfully used in this oxidative difunctionalization of alkenes. Good yields and selectivities