Related Experiment Video
Updated: May 31, 2026

Facile Preparation of (2Z,4E)-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
(E)-1-(5-Hy-droxy-2,2-dimethyl-2H-chromen-6-yl)-3-(3,4,5-trimeth-oxy-phen-yl)prop-2-en-1-one
Abstract:
The title compound, C(23)H(24)O(6), crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. The dihedral angles between the benzopyran ring and the α,β-unsaturated ketone unit and between the α,β-unsaturated ketone group and the benzene ring are 9.4 (10) and 12.96 (13)°, respectively, in mol-ecule A and 1.40 (17) and 4.44 (17)°, respectively, in mol-ecule B. The two meth-oxy groups at the meta positions of the benzene ring are close to being coplanar with the ring [C-O-C-C = 6.2 (3) and -1.4 (3)° in mol-ecule A and -4.2 (4) and 3.7 (3)° in mol-ecule B], whereas the third meth-oxy group, at the para position, is (+)-anti-clinal with respect to the benzene ring [C-O-C-C = 81.7 (3)°] in mol-ecule A and is (-)-synclinal with respect to the benzene ring [C-O-C-C = -103.2 (3)°] in mol-ecule B. In both independent mol-ecules, the hy-droxy group is involved in an intra-molecular O-H⋯O hydrogen bond.
Related Concept Videos
Structure and Nomenclature of Epoxides
Structure and Nomenclature of Ethers
Ethers are organic compounds with an ether functional group which is characterized by an oxygen atom connected to two — identical or different — alkyl, aryl, or vinyl groups. The C–O–C linkage in dimethyl ether — the simplest ether — has an approximately tetrahedral bond angle of 110.3 degrees. The oxygen atom is sp3- hybridized, with the C–O distance being about 140 pm.
Classification of Ethers
Based on their attached substituent groups, ethers can be classified into two...
Preparation of Epoxides
Epoxides result from alkene oxidation, which can be achieved by a) air, b) peroxy acids, c) hypochlorous acids, and d) halohydrin cyclization.
Epoxidation with Peroxy Acids
Epoxidation of alkenes via oxidation with peroxy acids involves the conversion of a carbon–carbon double bond to an epoxide using the oxidizing agent meta-chloroperoxybenzoic acid, commonly known as MCPBA. Since the O–O bond of peroxy acids is very weak, the addition of electrophilic oxygen of peroxy acids to...
Prochirality
Formation of Halohydrin from Alkenes
Structure and Nomenclature of Alcohols and Phenols
Alcohols are one of the most important functional groups in organic chemistry. The name of alcohol comes from the hydrocarbon from which it is derived. Alcohols are organic molecules containing the functional hydroxyl or –OH group directly bonded to carbon. Phenols have an OH group directly attached to a benzene ring. While alcohols are colorless, phenol is a white crystalline compound with a characteristic "hospital smell" odor.
As with other organic compounds, alcohols and phenols...

![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)