Related Experiment Video
Updated: Mar 16, 2026
ARL Spectral Fitting as an Application to Augment Spectral Data via Franck-Condon Lineshape Analysis and Color Analysis
Published on: August 19, 2021
Cr(III)-HMC (HMC = 5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane) Alkynyl Complexes: Preparation and
Sarah F Tyler1, Eileen C Judkins1, You Song2
1Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States.
Abstract:
Presented here is the chemistry of Cr(III) alkynyl complexes based on the rac-HMC and meso-HMC ligands (HMC = 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane). Thus far, two pairs of cis/trans-[Cr(rac/meso-HMC)(C2R)2]Cl (R = Ph, C2H/C2SiMe3) complexes have been synthesized from reactions between cis/trans-[Cr(rac/meso-HMC)Cl2]Cl and LiC2R. These complexes were characterized using single crystal X-ray diffraction, UV-vis spectroscopy, FT-IR spectroscopy, and fluorimetry. Single crystal X-ray diffraction studies revealed that these complexes adopt a pseudo-octahedral geometry. The electronic spectra of both the cis- and trans-[Cr(rac/meso-HMC)(C4R')2]Cl (R' = H or SiMe3) complexes exhibit d-d bands with pronounced vibronic progression associated with the asymmetric stretch of the Cr-bound C≡C bonds. All of these complexes are phosphorescent and show structured emissions originating from the ligand field excited states.
More Related Videos
09:45Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
12:19Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization
Published on: November 29, 2018
Related Concept Videos
02:38Electrophilic Addition to Alkynes: Halogenation
Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
01:32Aldehydes and Ketones with HCN: Cyanohydrin Formation Overview
02:35Electrophilic Addition to Alkynes: Hydrohalogenation
02:37Structure and Physical Properties of Alkynes
In nature, compounds containing both carbon and hydrogen are known as "hydrocarbons". Aliphatic hydrocarbons are compounds whose molecules contain saturated single bonds (i.e., alkanes) or unsaturated double or triple bonds. Alkenes contain carbon–carbon double bonds and have a structural formula CnH2n. Unsaturated hydrocarbons containing carbon–carbon triple bonds are called "alkynes" and are structurally represented by the formula CnH2n-2.
The...
02:34Preparation of Alkynes: Dehydrohalogenation
Alkynes can be prepared by dehydrohalogenation of vicinal or geminal dihalides in the presence of a strong base like sodium amide in liquid ammonia. The reaction proceeds with the loss of two equivalents of hydrogen halide (HX) via two successive E2 elimination reactions.
01:26Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation