Reaktion #327035
ord-53b9c43e0d0f4fadb2089b10b337e60e
Reaktionsbedingungen
Aufarbeitung
- 1Sonstigeazeotropically dried over a 4 hour period
- 2Trocknenthis toluene was dried with 1.5 g of n-BuLi solution
- 3TemperaturThe dried toluene was cooled to 82° C. with the oil jacket and PID controller
- 4workup.ADDITIONwas charged through the dip leg below the surface of the
- 5SonstigeThe feed line was then flushed with 75 mL of anhydrous toluene
Vorschrift
Toluene 2913 g, (3.4 liters, 31.61 mol) was charged to the reactor previously heated to 115° C. The toluene is refluxed and azeotropically dried over a 4 hour period; Karl Fischer moisture analysis indicated 21 ppm of residual H2O, this toluene was dried with 1.5 g of n-BuLi solution. The dried toluene was cooled to 82° C. with the oil jacket and PID controller operating the coiling coils both set at that temperature. Upon cooling to the set point temperature, 63 g n-BuLi solution (2M in cyclohexane, 0.162 mol) was charged through the dip leg below the surface of the gently agitated (300 rpm) toluene reaction mixture. The feed line was then flushed with 75 mL of anhydrous toluene. Next, 46.4 g of TMEDA (0.399 mol) was charged to the reactor through the subsurface feed line forming the characteristic bright red color of TMEDA-complexed benzyl lithium anion with concomitant off-gassing of butane. The subsurface line was flushed with a second 75 mL aliquot of anhydrous toluene via the metering pump. Reactor agitation was increased to 510 rpm and 1713 g of styrene (99+%, 16.45 mol) dissolved in 3070 g of toluene were fed over 360 minutes. The well-calibrated metering pump was programmed to feed at a constant rate of 13.3 g/min. Anhydrous cyclohexane (2×200 mL) was charged to the styrene feed system to flush the alumina bed. The styrene feed to the reactor was deemed complete when no further heat of reaction was observed generally signified by the closing of the automated control valve on the cooling coils. The set point of PID temperature controller was maintained at 82° C. and water was fed through the cooling coils as needed while the flow of the hot oil was altered to bypass the reactor jacket. The reaction mixture was quenched at 75° C. with a 50 mL aliquot of deoxygenated water resulting in a water-white turbid mixture. The reaction mixture was washed with deoxygenated water (3×650 mL). Phase cuts were rapid and required little settling time. Water and any rag or emulsion was removed through the bottom drain valve. During the course of the 6-hour feed, an aliquot was removed after 3 hours for analysis. The GPC area % analysis (excluding unreacted toluene) was as follows: Mn=226, Mw=247 Mz=281, PD=1.091 C15H16 70.3%; C23H24 20.1%; C31H32 6.4%; and higher oligomers 3.2%. The temperature of the oil jacket was increased to 130° C. while the control valve to the cooling coils turned off. Cyclohexane, residual moisture and toluene are distilled through a simple distillation head (1 atm.) until a pot temperature of 114° C. was observed. An aliquot was removed for analysis via GPC, the composition of the reaction product mixture (a telomer distribution of this invention) was as follows: C15H16 75.7%; C23H24 17.4%; C31H32 4.7%; and higher telomers 2.2%.