Isomeria Conformacional. fhmateo; 3 videos; 18 views; Last updated on Oct 11, Play all. Share. Loading Save. Empleo de la notación E-Z en la isomería Cis-Trans | | UPV – Duration: Universitat. Isomería de conformacional de alcanos y ciclo alcanos. Isomería conformacional (cis-trans): en dobles enlaces, en anillo.
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The anti conformation is lowest in energy, and the totally eclipsed conformation is highest in energy. The equatorial bonds are directed outward, toward the equator of the ring.
ISOMERIA by ismael castro on Prezi
Some groups are so bulky that they are extremely hindered in axial positions. When there are two carbon chains of the same length, the one that has the most substituents must be chosen to name the compound. Alkanes with an even number of carbons pack better than those conformzcional an odd number of carbons. Conformational Analysis of Propane Caption: Torsional energy of butane.
They are named by replacing the -ane ending of the alkane with -yl.
Some conformations can be more stable than others. Alcanos con par de C tienen p.
The simplest alkane is methane, CH4. Chair Conformation of Cyclohexane Caption: The bond angles are The axial bonds are directed vertically, parallel to the axis of the ring. Substituents on a carbon chain are called alkyl groups. Often, the longest chain with the most substituents is not obvious. Solution The longest carbon chain contains eight carbon atoms, so this compound is named as an octane.
To relieve ring strain, cyclopentane adopts the envelope conformation. The high reactivity of cyclopropanes is usomeria to the non-linear overlap of the sp3 orbitals.
The axial substituent interferes with the axial hydrogens on C3 and C5. In the symmetrical boat conformation of cyclohexane, eclipsing of bonds results in torsional strain.
The Newman conformavional is the best way to judge the stability of the different conformations of siomeria molecule. The only intermolecular force of nonpolar molecules are London dispersion forces which result from induced dipole attractions. The six-membered rings in cis- and trans-decalin assume chair conformations.
Propane is shown here as a perspective drawing and as a Newman projection looking down one of the carbon-carbon bonds. Esta interferencia es llamada interacciones 1,3-diaxial. Newman Projections of Butane Caption: The most stable conformation is the chair because it has all the C-H bonds staggered.
Same Length Chains Caption: Their physical properties resemble those of alkanes. The angle strain and the torsional strain in cyclopropane make this ring size extremely reactive. This isomegia of interference between two bulky groups is called steric strain or steric hindrance.
El Cis-1,3-dimetilciclohexano puede tener ambos grupos axiales o ecuatoriales. Two chair conformations are possible for cis-1,3-dimethylcyclohexane.
Sobre el proyecto SlidePlayer Condiciones de uso. All the C-H bonds are staggered in the chair conformation.
When a bond of propane rotates, the torsional energy varies much like it does in ethane, but with 0. Los substituyentes axiales interfieren con los H axiales del C 3 y C 5. This conformation is lower in energy and favored over the conformation with the methyl in the axial position.
Much like ethane the staggered conformations of propane is lower in energy than the eclipsed conformations. There is steric hindrance between these hydrogens so the molecule twists a little producing the twist boat conformation which is 1.
The ring strain of a planar cyclobutane results from two factors: The conformation of cyclopentane is slightly folded, like the conformaxional of an envelope. Conformational Analysis of Ethane Caption: Rotations about the center bond in butane give different molecular shapes. Cconformacional can adopt four non-planar conformations: The angle compression of cyclopropane isomeriw Nomenclature of Alkyl Groups Caption: Ieomeria from left to right gives the first branch on C2; numbering xonformacional right to left gives the first branch on C3, so we number from left to right.
Estructura y Estereoquímica de Alcanos
Conformations of Cyclohexane Caption: Pure conformers cannot be isolated in most cases, because the molecules are constantly rotating through all the possible conformations. Since the methyl group iisomeria more space than a hydrogen, the torsional strain will be 0. Groups like tert-butyl are so bulky that it will force the chair conformation where it is in the equatorial position, regardless of other groups present.