The Tetraphenylphosphonium bromide, with the CAS registry number 2751-90-8 and EINECS registry number 220-393-4, is also called phosphonium, tetraphenyl-, bromide (1:1). It is a kind of white to off-white crystalline powder, and belongs to the following product categories: Phosphonium Compounds; Greener Alternatives: Catalysis; Phase Transfer Catalysts; Phosphonium Salts. And the molecular formula of this chemical is C₂₄H₂₀BrP. What's more, it is usually used as phase-transfer catalyst.

The physical properties of Tetraphenylphosphonium bromide are as followings: (1)#H bond acceptors: 0; (2)#H bond donors: 0; (3)#Freely Rotating Bonds: 4; (4)Polar Surface Area: 0 Å².

Preparation of Tetraphenylphosphonium bromide: This chemical can be prepared by triphenylphosphane and bromobenzene. The reaction will need reagent aluminium chloride. The reaction time is 2 hours with temperature of 230°C, and the yield is about 57%. 

Uses of Tetraphenylphosphonium bromide: It can react with trans-3-Brom-5-(phenylsulfonyl)cyclopenten to produce Tetraphenylphosphonium-phenylsulfonylcyclopentadienid. And the yield is about 88%.  

You should be cautious while dealing with this chemical. It irritates eyes, respiratory system and skin. Therefore, you had better take the following instructions: Wear suitable protective clothing, and in case of contacting with eyes, rinse immediately with plenty of water and seek medical advice.

You can still convert the following datas into molecular structure:
(1)SMILES: [Br-].c1c(cccc1)[P+](c2ccccc2)(c3ccccc3)c4ccccc4
(2)InChI: InChI=1/C24H20P.BrH/c1-5-13-21(14-6-1)25(22-15-7-2-8-16-22,23-17-9-3-10-18-23)24-19-11-4-12-20-24;/h1-20H;1H/q+1;/p-1
(3)InChIKey: BRKFQVAOMSWFDU-REWHXWOFAF