Search results
Results From The WOW.Com Content Network
As such, cyclobutane is unstable above about 500 °C. The four carbon atoms in cyclobutane are not coplanar; instead, the ring typically adopts a folded or "puckered" conformation. [2] This implies that the C-C-C angle is less than 90°. One of the carbon atoms makes a 25° angle with the plane formed by the other three carbons.
In alkanes, optimum overlap of atomic orbitals is achieved at 109.5°. The most common cyclic compounds have five or six carbons in their ring. [6] Adolf von Baeyer received a Nobel Prize in 1905 for the discovery of the Baeyer strain theory, which was an explanation of the relative stabilities of cyclic molecules in 1885.
Norbornane (also called bicyclo[2.2.1]heptane). Unsubstituted cycloalkanes that contain a single ring in their molecular structure are typically named by adding the prefix "cyclo" to the name of the corresponding linear alkane with the same number of carbon atoms in its chain as the cycloalkane has in its ring.
Cyclobutane is a larger ring, but still has bent bonds. In this molecule, the carbon bond angles are 90° for the planar conformation and 88° for the puckered one. Unlike in cyclopropane, the C–C bond lengths actually increase rather than decrease; this is mainly due to 1,3-nonbonded steric repulsion.
Chemical nomenclature, replete as it is with compounds with very complex names, is a repository for some names that may be considered unusual. A browse through the Physical Constants of Organic Compounds in the CRC Handbook of Chemistry and Physics (a fundamental resource) will reveal not just the whimsical work of chemists, but the sometimes peculiar compound names that occur as the ...
The prismanes are a class of hydrocarbon compounds consisting of prism-like polyhedra of various numbers of sides on the polygonal base. Chemically, it is a series of fused cyclobutane rings (a ladderane, with all-cis/all-syn geometry) that wraps around to join its ends and form a band, with cycloalkane edges.
Rings may vary in size from three to many atoms, and include examples where all the atoms are carbon (i.e., are carbocycles), none of the atoms are carbon (inorganic cyclic compounds), or where both carbon and non-carbon atoms are present (heterocyclic compounds with rings containing both carbon and non-carbon).
The driving force of the reaction is the loss of strain from the cyclobutane ring. An organocatalytic Cope rearrangement was first reported in 2016. In this process, an aldehyde-substituted 1,5-diene is used, allowing "iminium catalysis" to be achieved using a hydrazide catalyst and moderate levels of enantioselectivity (up to 47% ee) to be ...