1-Bromo-4-pentylbenzene

Clear pale yellow liquid

General procedure: Under a nitrogen atmosphere, to a two-liter three-necked flask was added 236 g of p-dibromobenzene, 185 g of 1-bromopropane and 1 liter of anhydrous tetrahydrofuran; followed by addition of 204 g of zinc chloride, 36 g of magnesium powder and 18 Grams of acetylacetone iron. The mixture was heated to about 40 °C under stirring, the reaction was initiated after a few minutes, the reaction temperature was controlled at not more than 60 °C for 8 hours. The reaction mixture was then cooled to room temperature and quenched by stirring with 200 ml of water. The tetrahydrofuran solvent was recovered by distillation and the residue was diluted with 500 ml of toluene. The toluene layer was separated and washed twice with 200 ml of saturated brine and dried over anhydrous sodium sulfate Drying, filtration, filtrate recovery of toluene recovery, and then vacuum distillation, collecting at 94-97 °C / 10 mmHg to give 170 g of p-bromopyrophenyl. The yield was 85percent.2B 4-n-Pentylbromobenzene A mixture of 2A (77.1 g), hydrazine hydrate (46.4 g) and KOH (590 g) in diethylene glycol (250 ml) is heated at 130 °C for 2 h, the excess of hydrazine hydrate is distilled off and the temperature is raised to 200 °C for 2 h. The cooled mixture is poured into 18 percent HCl, the product is extracted into ether twice and the combined ethereal extracts are washed with water and dried (MgSO4). The solvent is removed in vacuo and the residue is distilled (bp 145-148 °C at 20 mm Hg) to yield a colourless liquid (58.1 g, 80 percent).(b) Synthesis of STR4 A reaction vessel was charged with 3.3 g of magnesium powder and a small piece of iodine. A small portion of a solution of 22.7 g of 4-pentyl-bromobenzene obtained in (a) above in 50 ml of tetrahydrofuran (THF) was added thereto, and the resultant mixture was heated with stirring. After foaming indicating the initiation of the reaction, the remainder of the above mentioned THF solution was added dropwise in such a manner that the resultant mixture was kept refluxed.

Intermediates of Liquid Crystals

Molecular Weight:227.14
XLogP3:4.8
Rotatable Bond Count:4
Exact Mass:226.03571
Monoisotopic Mass:226.03571
Heavy Atom Count:12
Complexity:104
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes