reflux and reactivity?

[Pimpo]

I've never read or heard about this, so I'll just try and ask it here. Does refluxing have any particular influence on chemical reactions, except constantly maintaining a certain temperature? E.g. could a reaction that normally is conducted in refluxing toluene (b.p. 110-112 °C) be done in xylene (b.p. 137 - 144 °C), being held as constantly as possible at a temperature of 110 °C or so?

[lugh]

Generally speaking, refluxing is used as a convenient means of controlling the temperature, since heating accelerates the rate of most chemical reactions by increasing the average kinetic energy of the molecules    These principle were first quantified by van't Hoff in 1884, d ln k/dT = Q/RT²    The system you propose would bee inconvenient in practice, though of course possible    One would normally reflux the xylene to increase the reaction rate, though naturally, this could bee counterproductive in certain cases  

[foxy2]

If I remember correctly the aproximate rule of thumb is that for every 10C increase in temperature the reaction rate doubles.

[Pimpo]

This was helpful. I guess I'll go the easy way first and use a higher reflux temperature, if that seems harmful, I'll try to constantly maintain a lower temperature (I might check into thermostates anyway, they can be useful for one or the other reaction).

[Rhodium]

When you reflux you automatically get great stirring - if you are heating xylene to 110°C you should compensate for that with good magnetic or overhead stirring.