It's not me that wants to replace it, it is the syntheses, many of them, and it is Henry reactions, specifically, I'm not a chemist but this is what I have read
Shulgin work, making 2cb
SYNTHESIS: A solution of 100 g of 2,5-dimethoxybenzaldehyde in 220 g nitromethane was treated with 10 g anhydrous ammonium acetate, and heated on a steam bath for 2.5 h with occasional swirling. The deep-red reaction mixture was stripped of the excess nitromethane under vacuum, and the residue crystallized spontaneously. This crude nitrostyrene was purified by grinding under IPA, filtering, and air-drying, to yield 85 g of 2,5-dimethoxy-beta-nitrostyrene as a yellow-orange product of adequate purity for the next step. Further purification can be achieved by recrystallization from boiling IPA.
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And his work on mescaline...notice that it is an alternate synthesis this time, instead of using cyclohexylanine he uses ammonium acetate.
SYNTHESIS: A solution of 20 g 3,4,5-trimethoxybenzaldehyde, 40 mL nitromethane, and 20 mL cyclohexylamine in 200 mL of acetic acid was heated on the steam bath for 1 h. The reaction mixture was then diluted slowly and with good stirring, with 400 mL H2O, which allowed the formation of a heavy yellow crystalline mass. This was removed by filtration, washed with H2O, and sucked as dry as possible. Recrystallization from boiling MeOH (15 mL/g) yielded, after filtration and air drying, beta-nitro-3,4,5-trimethoxystyrene as bright yellow crystals weighing 18.5 g. An alternate synthesis was effective, using an excess of nitromethane as solvent as well as reagent, if the amount of ammonium acetate catalysis was kept small. A solution of 20 g 3,4,5-trimethoxybenzaldehyde in 40 mL nitromethane containing 1 g anhydrous ammonium acetate was heated on the steam bath for 4 h. The solvent was stripped under vacuum and the residual yellow oil was dissolved in two volumes of hot MeOH, decanted from some insolubles, and allowed to cool. The crystals formed are removed by filtration, washed with MeOH and air dried yielding 14.2 g. of bright yellow crystals of beta-nitro-3,4,5-trimethoxystyrene. The use of these proportions but with 3.5 g ammonium acetate gave extensive side-reaction products even when worked up after only 1.5 h heating. The yield of nitrostyrene was, in this latter case, unsatisfactory.
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And I just saw a synth either..... here or another site, for making ammonium acetate from anhydrous ammonium gas and GAA.
Not a chemist but I read a lot and I think this will help you
You can read the whole of the chemistry in PiHKAL and TiHKAL on erowid site, and you can also see all of the rhodium site(snapshot) ..... And other places you can find the hive, vespiary, and hyperlab.
You ain't gotta be a chemist, to be able to cook a cake, especially when you have a grip of cookbooks at your fingertips