12/9/17 química la química es la ciencia que estudia la materia, su composición, la organización de los elementos que la forman las transformaciones que. Isomería C8H FR. Felipe Rodriguez. Updated 14 November Transcript. Isómeros. C8H A continuación,. observarán.. La fórmula. -Isomería estructural- Ejemplo: La isomería estructural es importante dentro del estudio de la química orgánica ya que permite conocer la.
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The methyl group is axial in one conformation, and equatorial in the other. For butane there will be two different staggered conformations: To make this website work, we log user data quuimica share it with processors. The simplest alkane is methane, CH4.
These conformations have equal energies, and they are present in equal amounts. Ethane has two sp3 carbons.
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To convert between these two conformations, the molecule must pass through the unstable half-chair conformation. Alcohols are compounds whose molecules have a hydroxyl. Conformational Analysis of Propane Caption: In this case both chairs have the same energy, and they are present in equal amounts.
The axial bonds are directed vertically, parallel to the axis of the ring. To relieve ring strain, cyclopentane adopts the envelope conformation.
Because of their smaller surface areas, branched alkanes have lower boiling points than unbranched alkanes. The more stable conformation has both methyl groups in equatorial positions.
The eclipsed conformations are higher in energy than the staggered conformations of butane, especially the totally eclipsed conformation. The staggered conformations are lower in energy than the eclipsed conformation because the staggering allows the electron clouds of the C-H bonds to be as far apart as possible. Conformational Energy Diagram of Cyclohexane Caption: Chair-chair interconversion of methylcyclohexane. Nomenclature of Alkyl Groups Caption: Interconversion between chair conformations require that cyclohexane go through its higher energy conformations.
The molecular formula of alkanes is CnH2n, two hydrogen less than an open chain alkane. Conformational Analysis of Butane Caption: Rotations about the center bond in butane give different molecular shapes.
Either of the chair conformations of trans-1,3-dimethylcyclohexane has isomedia methyl group in an axial position and one in an equatorial position. Among the staggered conformations, the anti is lower in energy because it has the electron clouds of the methyl groups as far apart as possible.
Chair Conformations of trans-1,3-Dimethylcyclohexane Caption: Conformational energy of cyclohexane. Numbering from left to orgsnica gives the first branch on C2; numbering from right to left gives the first branch on C3, so we jsomeria from left to right. Two chair conformations are possible for cis-1,3-dimethylcyclohexane.
Cyclobutane adopts the folded conformation to decrease the torsional strain caused by eclipsing hydrogens. The four hydrogen atoms are covalently bonded to the central carbon atom, with bond lengths of 1. This kind of interference between two bulky groups is called steric strain or steric hindrance. Compare this actual structure with the hypothetical planar structure in Figure Conformations of Cyclobutane Caption: Conformations of Cyclopropane Caption: The conformation of cyclobutane is slightly folded.
Ethane, the two-carbon alkane, is composed of two methyl groups with overlapping sp3 hybrid orbitals forming a sigma bond between them. They are named by replacing the -ane ending of the alkane with -yl. There are two possible geometric isomers for decalin: Angle strain and torsional strain account for the high reactivity of 4-membered rings. C5H12 C H 3 2 n-pentano iso-pentano neo-pentano Chapter 3. Angle strain in cyclopropane.
The high reactivity of cyclopropanes is due to the non-linear overlap of the sp3 orbitals. The chair conformation is most stable, followed by the twist boat. Viewed from the Newman quiimca, the chair conformation has no eclipsing of the carbon-carbon bonds.
Conformational Analysis of Ethane Caption: The different arrangement formed by rotations about a single bond are called conformations, and a specific is called conformer. Any carbon with four sigma bonds has an sp3 hybridization. Axial hydrogens are pointed straight up or down, parallel to the axis of the ring.