Search results
Results From The WOW.Com Content Network
In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist between two different elements: for example, in a carbonyl group between a carbon atom and an oxygen atom ...
Skeletal structural formula of Vitamin B 12.Many organic molecules are too complicated to be specified by a molecular formula.. The structural formula of a chemical compound is a graphic representation of the molecular structure (determined by structural chemistry methods), showing how the atoms are possibly arranged in the real three-dimensional space.
In fact, the carbon atoms in the single bond need not be of the same hybridization. Carbon atoms can also form double bonds in compounds called alkenes or triple bonds in compounds called alkynes. A double bond is formed with an sp 2-hybridized orbital and a p-orbital that is not involved in the hybridization. A triple bond is formed with an sp ...
In 1 H NMR spectroscopy, the hydrogen bonded to the carbon adjacent to double bonds will give a δ H of 4.5–6.5 ppm. The double bond will also deshield the hydrogen attached to the carbons adjacent to sp 2 carbons, and this generates δ H =1.6–2. ppm peaks. [14] Cis/trans isomers are distinguishable due to different J-coupling effect.
The polarity of C=O bond also enhances the acidity of any adjacent C-H bonds. Due to the positive charge on carbon and the negative charge on oxygen, carbonyl groups are subject to additions and/or nucleophilic attacks. A variety of nucleophiles attack, breaking the carbon-oxygen double bond, and leading to addition-elimination reactions.
In organic chemistry, allenes are organic compounds in which one carbon atom has double bonds with each of its two adjacent carbon atoms (R 2 C=C=CR 2, where R is H or some organyl group). [1] Allenes are classified as cumulated dienes. The parent compound of this class is propadiene (H 2 C=C=CH 2), which is itself also called allene.
A carbon–oxygen bond is a polar covalent bond between atoms of carbon and oxygen. [ 1 ] [ 2 ] [ 3 ] : 16–22 Carbon–oxygen bonds are found in many inorganic compounds such as carbon oxides and oxohalides , carbonates and metal carbonyls , [ 4 ] and in organic compounds such as alcohols , ethers , and carbonyl compounds .
The group may be represented as −CH 2 − or >CH 2, where the '>' denotes the two bonds. This stands in contrast to a situation where the carbon atom is bound to the rest of the molecule by a double bond, which is preferably called a methylidene group, represented =CH 2. [2] Formerly the methylene name was used for both isomers.