Potassium trispyrazolylborate, commonly abbreviated KTp, is the potassium salt with the formula :. This salt is the source of the
trispyrazolylborate ligand
In coordination chemistry, a ligand is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's electr ...
.
KTp is a white crystalline solid that is soluble in
polar solvents,
alcohols
In chemistry, an alcohol is a type of organic compound that carries at least one hydroxyl () functional group bound to a saturated carbon atom. The term ''alcohol'' originally referred to the primary alcohol ethanol (ethyl alcohol), which is ...
, and
water
Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...
. The synthesis of KTp involves
potassium borohydride
Borohydride refers to the anion , which is also called tetrahydroborate, and its salts. Borohydride or hydroborate is also the term used for compounds containing , where ''n'' is an integer from 0 to 3, for example cyanoborohydride or cyanotrihydr ...
and
pyrazole
Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. Pyrazole is a weak base, with p''K''b 11.5 ( ...
without a solvent.
:
The tris(pyrazolyl)borate forms octahedral coordination compounds with the formula M
psub>2 with first row transition metals. KTp also forms 1:1 complexes, for example it can be converted to K
pMo(CO)3
:
When K
pMo(CO)3is treated with
butyl nitrite
Butyl nitrite is the organic compound with the formula CH3(CH2)3ONO. It is an alkyl nitrite made from ''n''-butanol. Butyl nitrite is used recreationally as poppers. Synonyms include ''1-butyl nitrite'', n''-butyl nitrite'' and ''nitrous acid b ...
it yields the neutral orange complex TpMo(CO)
2NO.
:K
pMo(CO)3 BuONO→TpMo(CO)
2NO+CO+KOBu
References
{{boron compounds
Potassium compounds
Boron compounds
Pyrazoles