Search results
Results from the WOW.Com Content Network
Steric hindrance is a consequence of steric effects. Steric hindrance is the slowing of chemical reactions due to steric bulk. It is usually manifested in intermolecular reactions, whereas discussion of steric effects often focus on intramolecular interactions. Steric hindrance is often exploited to control selectivity, such as slowing unwanted ...
The protonation of substituted aniline is inhibited by steric hindrance. When protonated, the nitrogen in the amino group changes its orbital hybridization from sp 2 to sp 3 , becoming non-planar. This leads to steric hindrance between the ortho-substituted group and the hydrogen atom of the amino group, reducing the stability of the conjugate ...
Dispersion forces stabilizing a reactive moiety within a molecule is distinct from using steric bulk to protect that reactive moiety. Adding "steric hindrance" to a molecule's reactive site through bulky groups is a common strategy in molecular chemistry to stabilize reactive moieties within a molecule. [3]
Van der Waals strain is also called Van der Waals repulsion and is related to steric hindrance. [1] One of the most common forms of this strain is eclipsing hydrogen , in alkanes . In rotational and pseudorotational mechanisms
The tert-butyl effect is an example of steric hindrance. tert-Butyl as protecting group. A tert-butyl (tBu) ether is an acid-labile protecting group for alcohols. [3]
Like the substrate, steric hindrance affects the nucleophile's strength. The methoxide anion, for example, is both a strong base and nucleophile because it is a methyl nucleophile, and is thus very much unhindered.
The bite angle affect the steric crowding at the Rh atom that results from the interactions of the bulky backbone of the ligand with substrate. The wide bite angle that results from the backbone allows the five-coordinate [Rh(H)(diphosphine)CO(alkene)] intermediate to adopt a structure that relieves steric hindrance.
Increasing the steric bulk at the silicon center generally slows down reaction, potentially even suppressing reaction entirely when certain substituents are employed. In general, less bulky groups such as methyl or ethyl favor oxidation, while bulkier groups such as tert-butyl slow down or stop oxidation.