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The rule states that with the addition of a protic acid HX or other polar reagent to an asymmetric alkene, the acid hydrogen (H) or electropositive part gets attached to the carbon with more hydrogen substituents, and the halide (X) group or electronegative part gets attached to the carbon with more alkyl substituents. This is in contrast to ...
In the case of metal-alkenes and alkynes, the strengthening of the M–C 2 R 4 and M–C 2 R 2 bond is reflected in bending of the C–C–R angles which assume greater sp 3 and sp 2 character, respectively. [8] [9] Thus strong π backbonding causes a metal-alkene complex to assume the character of a metallacyclopropane. [10]
First, as the energy that is released by adding an electron to an isolated gaseous atom. The second (reverse) definition is that electron affinity is the energy required to remove an electron from a singly charged gaseous negative ion. The latter can be regarded as the ionization energy of the –1 ion or the zeroth ionization energy. [1]
Electronegativity is not a uniquely defined property and may depend on the definition. The suggested values are all taken from WebElements as a consistent set. Many of the highly radioactive elements have values that must be predictions or extrapolations, but are unfortunately not marked as such.
The following is a list of straight-chain alkanes, the total number of isomers of each (including branched chains), and their common names, sorted by number of carbon atoms. [ 1 ] [ 2 ] Number of C atoms
Alkenes that are particularly amenable to asymmetric hydrogenation often feature a polar functional group adjacent to the site to be hydrogenated. In the absence of this functional group, catalysis often results in low ee's. For some unfunctionalized olefins, iridium with P,N-based ligands) have proven effective, however. Alkene substrates are ...
K. Barry Sharpless was the first to develop a general, reliable enantioselective alkene dihydroxylation, referred to as the Sharpless asymmetric dihydroxylation (SAD). Low levels of OsO 4 are combined with a stoichiometric ferricyanide oxidant in the presence of chiral nitrogenous ligands to create an asymmetric environment around the oxidant.
There are several functional groups that contain an alkene such as vinyl group, allyl group, or acrylic group. Hydrocarbons may form charged structures: positively charged carbocations or negative carbanions. Carbocations are often named -um. Examples are tropylium and triphenylmethyl cations and the cyclopentadienyl anion.