Related Experiment Video
Updated: Feb 10, 2026
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Crystal structures of two new 3-(2-chloro-eth-yl)-r(2),c(6)-diarylpiperidin-4-ones
K Rajkumar1, S Sivakumar1,2, R Arulraj1
1Research and Development Centre, Bharathiar University, Coimbatore 641 046, Tamilnadu, India.
Abstract:
The syntheses and crystal structures of 3-(2-chloro-eth-yl)-r-2,c-6-di-phenyl-piperidin-4-one, C19H20ClNO, (I), and 3-(2-chloro-eth-yl)-r-2,c-6-bis-(4-fluoro-phen-yl)piperidin-4-one, C19H18ClF2NO, (II), are described. The piperidone ring adopts a chair conformation in (I), whereas a slightly distorted chair conformation is formed in (II). The dihedral angle between the mean plane of the phenyl rings is 59.1 (1)° in (I) and 76.1 (1)° in (II). The crystal packing features weak inter-molecular N-H⋯O hydrogen bonds in each structure.
Related Concept Videos
Criteria for Aromaticity and the Hückel 4n + 2 Rule
For the first time, Eric Hückel, a German chemical physicist, derived a set of structural features for a compound to be classified as aromatic. This is now known as Hückel’s rule or the 4n +...
Ionic Crystal Structures
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
meta-Directing Deactivators: –NO2, –CN, –CHO, –⁠CO2R, –COR, –CO2H
2° Amines to N-Nitrosamines: Reaction with NaNO2
![The Synthesis of [Sn10SiSiMe334]2- Using a Metastable SnI Halide Solution Synthesized via a Co-condensation Technique](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F54498.jpg&w=3840&q=50)
