Samarium(II) iodide mediated intramolecular reductivecoupling of carbonyl groups and alkynes in the presence of HMPA and t-BuOH was successfully performed to provide cyclized products. Some cyclic compounds containing a heteroatom such as oxygen or nitrogen were also efficiently prepared by this coupling reaction.
1,1,1,3,3,3-Hexafluoro-2-propanol (HFIP)-Assisted Catalyst-Free Sulfonation of Allylic Alcohols with Sulfinyl Amides
作者:Zhen Luo、Zheng-Qiang Liu、Ting-Ting Yang、Xin Zhuang、Chuan-Ming Hong、Fei-Fei Zou、Zhi-Yong Xue、Qing-Hua Li、Tang-Lin Liu
DOI:10.1021/acs.orglett.1c04206
日期:2022.1.21
A highly regioselective and catalyst-free sulfonation of allylic alcohols with sulfinyl amides has been realized. Such a mix-and-go procedure provides a convenient approach to synthetically various allylic sulfones under mild reaction conditions. Furthermore, this novel reaction shows ample substrate scope and outstanding functional group tolerance and could also be scaled-up. Meanwhile, it is the
exclusive asymmetric reduction of CO bonds of 2-arylidene four-, five-, six-, and seven-membered cycloalkanones has been studied systematically. The asymmetric transfer hydrogenation was performed using a robust and commercially available chiral diamine-derived ruthenium complex as a catalyst and HCOOH/Et3N as a hydrogen source under mild conditions, giving 51 examples of chiral exocyclic allylic alcohols
已经系统地研究了2-芳基四,五,六和七元环烷烃的C O键的排他不对称还原。在温和条件下,使用稳固且可商购的手性二胺衍生钌络合物作为催化剂,HCOOH / Et 3 N作为氢源,进行不对称转移氢化,给出了51种示例手性环外烯丙基醇,收率高达96%, 99%ee。该方法也适用于抗炎洛索洛芬和天然产物(-)-goniomitine的活性中间体的克级合成。
Rh(I)-catalyzed ring-opening of cyclobutanols via C–C bond activation: Synthesis of cis-olefin with a remote aldehyde
作者:Yu Nie、Jianzhong Chen、Wanbin Zhang
DOI:10.1016/j.tet.2019.130563
日期:2019.9
A Rh(I)-catalyzed ring-opening of cyclobutanols has been developed with ring opening products bearing cis-olefin and a remote aldehyde. Various substrates bearing different substituted aryl groups, heterocyclic groups and alkyl groups were compatible with the mild reaction conditions. A β-C elimination pathway was proposed based on the results of preliminary mechanistic studies.
Preparation of Polycyclic Systems by Sequential 5-<i>E</i><i>xo</i>-<i>D</i><i>igonal</i> Radical Cyclization, 1,5-Hydrogen Transfer from Silicon, and 5-<i>E</i><i>ndo</i>-<i>T</i><i>rigonal</i> Cyclization
作者:Derrick L. J. Clive、Wen Yang、Aaron C. MacDonald、Zhongren Wang、Michel Cantin
DOI:10.1021/jo001124x
日期:2001.3.1
diagonal cyclization, and the resulting vinyl radical abstracts hydrogen from silicon to afford a silicon-centered radical. This radical closes in a 5-endo trigonal manner to generate radicals of type 4, which are reduced (4 --> 5) by stannane, except when the starting acetylene carries a terminal trimethylstannyl group. In this case, radicals 4 expel trimethylstannyl radical to afford vinyl silanes