The [4+1] cycloaddition reaction of bifunctional amino reagents has been achieved with in situ formed aza‐ortho‐quinonemethides. Specifically, N‐(tosyloxy)carbamates were used as an N1 synthon and bifunctional amino reagents for this transformation, which provides a metal‐free, catalyst‐free, and oxidant‐free strategy to form nitrogen‐nitrogen bonds.
A transition-metal-free method for the synthesis of indolines has been developed. In the presence of K2CO3, the cyclization reaction of N-(ortho-chloromethyl)arylamides and iodonium ylides proceeded smoothly at room temperature in moderate to good yields.
已经开发了用于合成二氢吲哚的无过渡金属的方法。在K 2 CO 3的存在下,N-(邻-氯甲基)芳基酰胺和碘鎓碘化物的环化反应在室温下以中等至良好的收率顺利进行。
Formal [4+1] Cycloaddition of<i>o</i>‐Aminobenzyl Chlorides with Isocyanides: Synthesis of 2‐Amino‐3‐Substituted Indoles
作者:Jacobus A. W. Jong、Xu Bao、Qian Wang、Jieping Zhu
DOI:10.1002/hlca.201900002
日期:2019.3
Reaction of substituted o‐aminobenzyl chlorides with isocyanides in the presence of a weak base (NaHCO3) at room temperature afforded the diversely functionalized 2‐aminoindoles in good to excellent yields. A formal [4+1] cycloaddition of the in situ generated aza‐ortho‐xylylenes with isocyanides accounted for the reaction outcome.
Accessing benzooxadiazepines<i>via</i>formal [4 + 3] cycloadditions of aza-<i>o</i>-quinone methides with nitrones
作者:Yong-Sheng Zheng、Liang Tu、Li-Mei Gao、Rong Huang、Tao Feng、Huan Sun、Wen-Xuan Wang、Zheng-Hui Li、Ji-Kai Liu
DOI:10.1039/c8ob00201k
日期:——
An unprecedented and efficient [4 + 3] cycloaddition of N-(ortho-chloromethyl)aryl amides with nitrones has been developed. This approach provides easy access to a series of seven-membered benzooxadiazepine derivatives in good to excellent yields (up to 99% yield) under mild reaction conditions.
Diversity-oriented synthesis of 1,2,3,5-tetrahydrobenzo[e][1,2,4]oxadiazepines and 2,3-dihydro-1H-benzo[e][1,2,4]triazepines by base-induced [4 + 3] annulation reactions
作者:Wuyan Long、Shuangqun Chen、Xiaohong Zhang、Ling Fang、Zhiyong Wang
DOI:10.1016/j.tet.2018.09.004
日期:2018.10
The base-induced formal [4 + 3] annulation reactions of N-(ortho-chloromethyl)aryl amides with nitrones or hydrazonoyl chlorides have been reported. When nitrones are used as the 1,3-dipole, the corresponding reaction afforded a series of 1,2,3,5-tetrahydrobenzo[e][1,2,4]oxadiazepine derivatives. Highly functionalized 2,3-dihydro-1H-benzo[e][1,2,4]triazepine derivatives were also synthesized via an
已经报道了碱诱导的N-(邻氯甲基)芳基酰胺与硝酮或酰肼基氯化物的正式[4 + 3]环化反应。当将硝酮用作1,3-偶极时,相应的反应得到一系列1,2,3,5-四氢苯并[ e ] [1,2,4]恶二氮杂衍生物。还通过N-(邻-氯甲基)芳基酰胺和酰基之间空前的串联氮杂-迈克尔加成/重排芳构化反应合成了高度官能化的2,3-二氢-1 H-苯并[ e ] [1,2,4]三氮杂卓衍生物氯化物。