Search results
Results from the WOW.Com Content Network
Compounds or mixtures that cannot form an adduct because of steric hindrance are called frustrated Lewis pairs. Adducts are not necessarily molecular in nature. A good example from solid-state chemistry is the adducts of ethylene or carbon monoxide of CuAlCl 4. The latter is a solid with an extended lattice structure.
Many adducts violate the octet rule, such as the triiodide anion: I 2 + I − → I − 3. The variability of the colors of iodine solutions reflects the variable abilities of the solvent to form adducts with the Lewis acid I 2. Some Lewis acids bind with two Lewis bases, a famous example being the formation of hexafluorosilicate: SiF 4 + 2 F ...
Lewis structures – also called Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDs) – are diagrams that show the bonding between atoms of a molecule, as well as the lone pairs of electrons that may exist in the molecule. [1][2][3] A Lewis structure can be drawn for any covalently bonded ...
Boron trifluoride is a versatile Lewis acid that forms adducts with such Lewis bases as fluoride and ethers: CsF + BF3 → Cs [BF4] O (CH 2 CH 3) 2 + BF3 → BF3·O (CH2CH3)2. Tetrafluoroborate salts are commonly employed as non-coordinating anions.
Structure of Lewis acidic antimony compounds. Lewis acidic antimony complexes with a variety of oxidation states and coordination numbers are known. Several salient examples are introduced below. FIA indicates fluoride ion affinity. δ indicates the 31 P NMR shift of OPEt 3 adducts (Gutmann–Beckett method).
Compared to trimethylaluminium and trimethylgallium, InMe 3 is a weaker Lewis acid.It forms adducts with secondary amines and phosphines. [5] A complex with the heterocyclic triazine ligand (Pr i NCH 2) 3 forms a complex with 6-coordinate In, where the C-In-C angles are 114°-117° with three long bonds to the tridentate ligand with N-In-N angles of 48.6° and long In-N bonds of 278 pm. [6]
AlH 3 readily forms adducts with strong Lewis bases. For example, both 1:1 and 1:2 complexes form with trimethylamine. The 1:1 complex is tetrahedral in the gas phase, [30] but in the solid phase it is dimeric with bridging hydrogen centres, (N(CH 3) 3 Al(μ-H)) 2. [31] The 1:2 complex adopts a trigonal bipyramidal structure. [30]
Non-nucleophilic. Weak. v. t. e. A frustrated Lewis pair (FLP) is a compound or mixture containing a Lewis acid and a Lewis base that, because of steric hindrance, cannot combine to form a classical adduct. [1] Many kinds of FLPs have been devised, and many simple substrates exhibit activation. [2][3] The discovery that some FLPs split H 2[4 ...