Synthese und Kristallstruktur der Benzyltriphenylphosphonium-bromide: [C₆H₅-CH₂P(C₆H₅)₃]⁺Br^-CH₂Cl₂ und [C₆H₅-CH₂P(C₆H₅)₃]⁺Br₃ ^- / Synthesis and Crystal Structures of (Benzyl)triphenylphosphonium Bromides, [C₆H₅-CH₂P(C₆H₅)₃]⁺Br^-CH₂Cl₂ and [C₆H₅-CH₂P(C₆H₅)₃]⁺Br₃ ^-

Abstract

(Benzyl)triphenylphosphonium bromide, [C 6 H 5 -CH 2 P(C 6 H 5 ) 3 ] + Br - (CH 2 Cl 2 ) (1) has been prepared by the reaction of triphenylphosphine with benzylbromide and its structure determined. The colorless crystals are triclinic, space group P1̄, Z = 2, a = 976.0(3), b = 1069.0(3), c = 1226.1(4) pm, α = 94.13(3), β = 104.70(3), γ = 100.14(3)°. The lattice contains Br - anions and [C 6 H 5 -CH 2 P(C 6 H 5 ) 3 ] + cations. [C 6 H 5 -CH 2 P(C 6 H 5 ) 3 ]Br 3 (2) has been obtained by treating compound 1 with equimolar quantities of elemental bromine in methylene chloride solution. The red crystals of 2 are monoclinic, space group P2 1 /c, Z = 4, a = 917.9(2), b = 1022.6(2), c = 2573.6(5) pm, β = 99.11(2)°, and comprise[C 6 H 5 -CH 2 P(C 6 H 5 ) 3 ] + cations and linear, slightly asymmetrical Br 3 - anions with bromine-bromine distances of 246.19(11) and 263.69(11) pm.