Swim finally gave this reaction a try following chromic's writeup on rhodium.ws and had some success but seemingly low yields. Swim ran a 1mol rxn and finished with just under 70g of NaGHB(s).
Swim used ACS grade NaNO2, OTC GABA (that had been tested against a small quantity of ACS grade GABA and was found to have identical solubilities in hot/cold dH2O and EtOH) and OTC muriatic acid.
Reagents where dissolved w/ mag stirring in 300mL dH2O and chilled to below 0°C in an ice-water batch. Acid was added via an addition funnel (was worried a pressure-eq funnel would be needed, but vacuum never seemed to build up) and fumes were vented far away from SWIM using tubing.
Acid was added over the course of two hours.. went very slowly at first, keeping the buildup of yellow-brown gas under control in the rxn flask. Near the end, gas evolution diminshed, and the last 1/3rd of acid was added pretty quickly (over 15-20min). After acid addition, flask sat and stirred and bubbled at 0°C for an hour. At this point, stirring was turned off, and the rxn flask was allowed to sit overnight for 14hrs.
Upon returning, the temp was around 20°C and no bubbling was observed. Swim proceeded to setup flask for simple distillation and began steam distilling off GBL/water, but noticed as the temp increased and stirring was turned back on small gas bubbles formed in the flask (perhaps hadn't finished reacting yet?) Steam distillation continued into NaCl precip. was observed. Distillate was refluxed with ACS NaOH, boiled with 5% activated charcol, filtered, heated to 140-150degC to boil off H2O/excess lactone, and poured into pyrex dish...giving 20g or so of NaGHB. Product was hard, pure white in colour, looked identical to the product of a NaOH/99.9% GBL rxn (yay!). Had a slight tangy aftertaste however (butryic acid maybe?)
Remainder of aqueous was extracted with 5x230mL washes of ethyl acetate. Solvent was removed under vacuum, then swim was planning on distilling off the GBL, but when the temp hit around 50°C in the distillation flask, swim's vacuum failed (one of the joints in the apparatus was the wrong size, and was being held together with parafilm which seemed to melt off ruining the seal).
Distillation was continued until 92°C at 1 atm, then the 48mL of resulting yellowish/brown liquid was reacted with NaOH, boiled with activated carbon, filtered, re-heated to 140-150 °C then poured into a pyrex dish and allowed to harden into NaGHB. Yield was 48g of slightly brownish NaGHB. Swim was worried about product purity, but it tasted and smelled _fine_ (even better then the white NaGHB recovered earlier). Of course was bioassayed and +ve results (no difference in required dosing noted to 0.1 of a gram).
So... 70g yield. swim was expecting close to double that from this reaction.. what went wrong? Rxn not go to completion at the beginning? Solvent washes done incorrectly? Toss some ideas at swim as he is planning on doing the 3mol version of the run soon.