Calculator Inputs
Reaction Planning Graph
This Plotly graph shows estimated isolated product mass and unreacted Grignard excess across reagent equivalents.
Example Data Table
| Example Case | Grignard Reagent | Substrate | Equiv. | Conversion | Theoretical Yield (g) | Estimated Isolated Yield (g) |
|---|---|---|---|---|---|---|
| A | Phenylmagnesium bromide | Benzaldehyde | 1.20 | 88% | 16.86 | 13.15 |
| B | Methylmagnesium bromide | Acetophenone | 1.50 | 84% | 11.42 | 8.91 |
| C | Ethylmagnesium chloride | Cyclohexanone | 1.10 | 79% | 9.77 | 7.04 |
Formula Used
1) Active moles of each reactant
Active moles = (Mass / Molecular weight) × (Purity / 100)
This adjusts charged mass to chemically active material. It is useful when commercial solutions, damp solids, or partially pure reagents are used.
2) Limiting reactant basis
Limiting basis = minimum(Grignard active moles / Grignard equivalents, Substrate active moles / Substrate equivalents)
This compares both materials on a normalized stoichiometric basis so the program can identify which component controls maximum conversion.
3) Theoretical product moles and mass
Theoretical product moles = Limiting basis × Product stoichiometric coefficient
Theoretical product mass = Theoretical product moles × Product molecular weight
These values estimate the highest possible amount of isolated product if the reaction proceeds ideally.
4) Expected converted and isolated product
Expected converted mass = Theoretical mass × (Expected conversion / 100)
Estimated isolated mass = Theoretical mass × (Estimated isolated yield / 100)
The conversion term reflects reaction progress. The isolated yield term reflects losses during workup and purification.
5) Reagent solution and solvent estimates
Reagent volume (L) = Grignard active moles / Solution molarity
Suggested solvent (mL) = Substrate mass × Solvent factor
Estimated quench (mL) = Suggested solvent × Quench multiplier
These are planning aids for reaction setup and safe workup scaling.
How to Use This Calculator
- Enter the reagent, substrate, and target product names.
- Provide charged masses, molecular weights, purities, and intended equivalents.
- Set expected conversion and isolated yield based on literature or lab history.
- Enter solution molarity and solvent assumptions for setup planning.
- Press Calculate Reaction to display the result block above the form.
- Review limiting reactant, yield estimates, excess reagent, and solvent guidance.
- Use the chart to compare how changing Grignard equivalents affects isolated mass.
- Export the calculations using the CSV or PDF buttons.
FAQs
1) What does this calculator estimate?
It estimates active moles, limiting reactant, theoretical yield, isolated yield, reagent excess, solution volume, solvent needs, and a simple efficiency picture for Grignard additions.
2) Why is purity included?
Grignard reagents and substrates may not be fully active. Purity correction avoids overstating moles and gives a more realistic estimate for theoretical and isolated product output.
3) Does it handle every Grignard mechanism?
No. It is a stoichiometric planning calculator. It does not model side reactions, aggregation, moisture loss, competing reduction, or chemoselectivity issues.
4) What should I enter for equivalents?
Use the stoichiometric ratio intended in your procedure. Many Grignard additions use a slight reagent excess to improve conversion when some reagent is lost or quenched.
5) Is the solvent estimate exact?
No. Solvent usage depends on mixing, heat removal, concentration targets, and equipment geometry. The value here is a planning guide, not a fixed operating requirement.
6) What is the difference between conversion and isolated yield?
Conversion describes how much starting material reacts. Isolated yield reflects how much purified product you actually recover after quench, extraction, drying, and purification.
7) Can I use this for scale-up?
Yes, for initial planning. Large-scale Grignard chemistry still needs thermal safety review, controlled addition strategy, agitation checks, and validated quench procedures.
8) Does the graph optimize the reaction automatically?
No. The graph visualizes how estimated isolated mass and reagent excess shift with equivalents. Final optimization still depends on experiment, kinetics, and impurity control.