Tools · Synthesis

Reaction Scale Calculator

Pick a stored reaction, fix one reagent's amount, get every other reagent's quantity by stoichiometric equivalents. Solvent volume derived from your substrate concentration. Densities + molar masses come from our molecule database.

Reaction

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Henry reaction (nitroaldol addition)

RCH₂NO₂ + R'CHO → R'CH(OH)CH(NO₂)R

Base-catalysed addition of a nitroalkane to an aldehyde or ketone to give a β-nitro alcohol. Key C-C bond-forming step in the Knoevenagel-Henry route to β-nitrostyrenes (e.g. P2NP).

Conditions: Glacial acetic acid (or 80 % aq. AcOH for milder conditions); primary amine catalyst (n-butylamine, 5–20 mol%). Run at 20–25 °C in the dark for the slow variant, or at reflux (~118 °C glacial) for the faster Knoevenagel variant. Workup: pour onto cold water, filter the yellow nitroalkene, recrystallise from MeOH or EtOH.

Expected yield: 60–75 %
Expected duration: 5–14 days at RT in the dark; 3–6 h at reflux (Knoevenagel variant)

Mechanism reference ↗

Anchor reagent — fix this amount, scale everything else Substrate concentration · M

Amount r Unit

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Reactants

Reactants for Henry reaction (nitroaldol addition): stoichiometric quantities derived from the anchor amount.
Reagent	Equiv	Moles · mmol	Mass · g	Volume · mL
Nitroethane 79-24-3 · C2H5NO2	1.0	10.00	0.751	0.72
Benzaldehyde 100-52-7 · C7H6O	1.0	10.00	1.061	1.01

Catalyst

Catalyst for Henry reaction (nitroaldol addition): stoichiometric quantities derived from the anchor amount.
Reagent	Equiv	Moles · mmol	Mass · g	Volume · mL
109-73-9 109-73-9 · C4H11N	0.1	1.00	0.073	0.10

Solvent

Solvent for Henry reaction (nitroaldol addition): stoichiometric quantities derived from the anchor amount.
Reagent	Equiv	Moles · mmol	Mass · g	Volume · mL
Acetic Acid 64-19-7 · C2H4O2	—	346.38	20.800	20.00

Product

Product for Henry reaction (nitroaldol addition): stoichiometric quantities derived from the anchor amount.
Reagent	Equiv	Moles · mmol	Mass · g	Volume · mL
Phenyl-2-Nitropropene 705-60-2 · C9H9NO2	1.0	10.00	1.632	—

Expected isolated yield

What you should actually weigh out of the recrystallisation flask, scaled from the limiting reactant via the canonical-procedure yield window.

Product: Phenyl-2-Nitropropene 705-60-2 · C9H9NO2
Theoretical max: 1.63 g (10.00 mmol)
Expected isolated · 60–75 % yield: 0.98 – 1.22 g

Stoichiometry: moles_X = (moles_anchor / equiv_anchor) × equiv_X. Mass = moles × MW; volume = mass / ρ. Solvent volume = total reactant moles ÷ substrate concentration.