P2P via Pb success

[zero_nrg]

100 mmol phenylacetic acid (homemade via carbonation of the Grignard reaction)
150 mmol lead acetate ( made via GAA + PbO)

I decided to give this reaction a try without the use of vacuum as per xtaldoc as the parts for my homemade stainless steel condenser are on order.  This should be done with a proper themometer but I was just too anxious to give it a go.
The phenylacetic acid was dissolved in the glacial acetic acid prior to mixing with the lead oxide (exothermic).  A 100 ml RB distilling flask was placed in a beaker with sand which covered most of the RBF (don't have a mantle that small).  The beaker was set on a hot plate which was variac controlled.  The vaccum take-off on the receiving end of the distillation was run into tubing which was placed outdoors.  When the temp reached 155C the lead oxide (which was still present as small yellowish granules) seemed to turm white.  At 185C there was alot of bubbling of the liquid, but no condensation.  At 225C a barely perceptible cloudy scum formed on the surface of the liquid.  At 252C water started to condense very slowly- one drop every 8 seconds or so.  At 260C water still condensing and I pulled my thermometer out as it has a 260 degree max.  So at this point I can only guess as to  the temperature.  Water seemed to distill for approx. 1.75 hrs.  and I got impatient and turned up the variac to 140 volts and 100%.  Shoudn't have done that as the beaker started to melt into my hotplate.  Turned the variac down to 120volts and 100%.  After 2 hrs the P2P started to distill out into the condenser and there was no mistaking the odor.  After 2 hrs 13 min.  a crust formed on the surface of the liquid in the distilling flask which, as described by xtaldoc, appears like a the lunar surface.  This grayish solid layer had alot of crater like holes in it and you could see the distillate boiling up through these small holes.  Eventually the solid layer cracked. Also some white smoke could be seen coming from the distilling flask intermittently - but only for a few seconds at a time.  Could not run this to completion as I had appointments elsewhere and distillation was stopped after 2.5 hrs.  After seperation I have about 2.5 ml distillate.  Will try this under vacuum and run it to completion with proper equipment. Waste to be discarded in environmentally benign manner.  This synth really works -very cool.  -zero

[n00dle]

would silicon glue effect this rxn? assuming one's thermometer is a thermocouple which has been siliconed into the top of his/her's stainless steel column?

[ning]

Now try using calcium acetate instead! Yummy!

[zero_nrg]

would silicon glue effect this rxn? assuming one's thermometer is a thermocouple which has been siliconed into the top of his/her's stainless steel column?
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Assuming when you mention "stainless steel column" that you´re talking about the reaction vessel (or perhaps distilling column).  No matter, if that´s the case, and you planned on following xtaldocs write-up, how would you know when to turn down the heat so that you reach the reaction temperature slowly as per xtaldoc:

Rapid heating to approx 185°C, then turn the gas down (vac from the start) so the initiation point is smooth (otherwise it'll puke into receiver) at about 195°C or so.

Also, assuming you´re plan is to run this under vac, if the silicone glue fails your yields will suck.  I´ve tried this both ways and vac is better.  Check out the high temp RTD probe at "probes unlimited" website.  They are a mfr, will make them in any length you want, and the probes are inexpensive and accurate.  Hook the probe up to you digital multimeter and read the resistance on your nearby Excel spreadsheet to find the temp.  The probes are attatched to your SS reaction vessel with a SS compression fitting. 
Question for wise bees:  when this reaction starts cranking, and quantities of CO2 are rapidly evolving from the reaction along with the white smoke (lead compounds I´m guessing), can the smoke be bubbled through something (water etc) to remove it before it enters the vacuum?  The vac isn´t high enough to boil water (128mm if I recall) so I´m thinking water might be on option.  Any ideas? Yes, a tube furnace would be better:)  -zero