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Phosphorus pentabromide is a reactive, yellow solid of formula P Br 5, which has the structure [PBr 4] + Br − (tetrabromophosphonium bromide) in the solid state but in the vapor phase is completely dissociated to PBr 3 and Br 2.
For example, with a Lewis acid such as boron tribromide it forms stable 1 :1 adducts such as Br 3 B · PBr 3. At the same time PBr 3 can react as an electrophile or Lewis acid in many of its reactions, for example with amines. An important reaction of PBr 3 is with alcohols, where it replaces an OH group with a bromine atom to produce an alkyl ...
Reactions can occur between a solid reactant coupled with either a gas, liquid, or other solid. If the reactants, intermediates, and products are all solids, it is known as a solid flame. [ 2 ] If the reaction occurs between a solid reactant and a gas phase reactant, it is called infiltration combustion.
Using higher temperatures during the reaction can lead to favoring of the Arbuzov product. The reaction of α-iodoketones give only the Arbuzov product. [7] Other methods of producing β-ketophosphonates have been developed. [8] The reaction of trivalent phosphorus compounds with alkyl fluorides is abnormal. One example of this reactivity is ...
The solid-state reaction route is the most widely used method for the preparation of polycrystalline solids from a mixture of solid starting materials. Solids do not react together at room temperature over normal time scales and it is necessary to heat them to much higher temperatures, often to 1000 to 1500 °C, in order for the reaction to occur at an appreciable rate.
The IUPAC definition of a solid solution is a "solid in which components are compatible and form a unique phase". [3]The definition "crystal containing a second constituent which fits into and is distributed in the lattice of the host crystal" given in refs., [4] [5] is not general and, thus, is not recommended.
Weinreb and Nahm originally proposed the following reaction mechanism to explain the selectivity shown in reactions of the Weinreb–Nahm amide. Their suggestion was that the tetrahedral intermediate (A below) formed as a result of nucleophilic addition by the organometallic reagent is stabilized by chelation from the methoxy group as shown. [1]
In the image shown at the right one molecule of H 2 O acts as a base and gains H + to become H 3 O + while the other acts as an acid and loses H + to become OH −. Another example is illustrated by substances like aluminium hydroxide, Al(OH) 3. () + ()