Related Experiment Video

Updated: Jun 1, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
19:58

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Published on: July 30, 2017

1,1'-Dimethyl-4,4'-[(2,4-diphenyl-cyclo-butane-1,3-di-yl)dipyridinium-(E)-1-methyl-4-styrylpyridinium-benzene-sulfona

Hoong-Kun Fun, Chanasuk Surasit, Kullapa Chanawanno

    Acta Crystallographica. Section E, Structure Reports Online
    |May 18, 2011
    PubMed

    More Related Videos

    Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles11:45

    Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles

    Published on: August 22, 2018

    Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions04:38

    Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions

    Published on: July 28, 2022

    Related Concept Videos

    NMR Spectroscopy of Benzene Derivatives01:37

    NMR Spectroscopy of Benzene Derivatives

    Simple unsubstituted benzene has six aromatic protons, all chemically equivalent. Therefore, benzene exhibits only a singlet peak at δ 7.3 ppm in the 1H NMR spectrum. The observed shift is far downfield because the aromatic ring current strongly deshields the protons. Any substitution on the benzene ring makes the aromatic protons nonequivalent, and the protons split each other. The peak is, therefore, no longer a singlet and the splitting pattern and their associated coupling constants depend...
    Nomenclature of Aromatic Compounds with Multiple Substituents01:11

    Nomenclature of Aromatic Compounds with Multiple Substituents

    When more than one substituent is present on the benzene ring, the IUPAC nomenclature depends on the number of substituents present.
    For disubstituted benzene derivatives, with two groups attached to the benzene ring, three constitutional isomers are possible. For example, consider dimethyl benzene, often called xylene, where the second methyl group can be substituted at the second, third, or fourth carbon. The relative position of the substituents is represented by prefixes ortho, meta, or...
    π Molecular Orbitals of 1,3-Butadiene01:24

    π Molecular Orbitals of 1,3-Butadiene

    Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
    The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the number...
    Aromatic Hydrocarbon Cations: Structural Overview01:18

    Aromatic Hydrocarbon Cations: Structural Overview

    Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
    Removing one hydrogen from the intervening CH2 group with both...
    Structure of Benzene: Molecular Orbital Model01:18

    Structure of Benzene: Molecular Orbital Model

    According to the molecular orbital (MO) model, benzene has a planar structure with a regular hexagon of six sp2 hybridized carbons. As shown in Figure 1, each carbon is bonded to three other atoms with C–C–C and H–C–C bond angles of 120°. The C–H bond length is 109 pm, and the C–C bond length is 139 pm which is midway between the single bond length of sp3 hybridized carbons (154 pm) and sp2 hybridized carbons (133 pm).
    Frost Circles for Different Conjugated Systems01:18

    Frost Circles for Different Conjugated Systems

    The inscribed polygon method is consistent with Hückel’s 4n + 2 rule and helps to learn whether the given cyclic compound is aromatic or not. The compound is stable and aromatic if every bonding molecular orbital (MO) is completely filled with a pair of electrons. However, if the non-bonding or antibonding orbitals are filled with electrons, the compound is unstable and not aromatic. Consider the Frost circle diagrams for cycloalkenes containing 4 to 8 carbons.