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Buchwald–Hartwig amination: 4-Bromo-2-nitroanisole → cis-3,5-Dimethyl-1-[4-(methyloxy)-3-nitrophenyl]piperazine

90% yield, run at 100 °C, as recorded by experimental reaction archive. The written procedure is below.

verified record, 90% yield recorded, Not balanced as written, From experimental reaction archive

Reagents, catalysts and solvents are in the table below.

The atoms, from reactants to products

COCCCCNCCCNCCCCCNOOBr
Reactants · 1/6
breakingformingbond order changesmapped atom that changes

Drawn from the record's atom map: which bonds break and which form between the reactants and products the source listed. It shows a change in connectivity, not a simulated trajectory and not a mechanism.

What was in the flask

RoleSpeciesFormulaYield
Reactant4-Bromo-2-nitroanisoleC₇H₆BrNO₃—
Reactantrel-(2R,6S)-2,6-dimethylpiperazineC₆H₁₄N₂—
ReagentCesium carbonateCCs₂O₃—
CatalystBinap, (A+-)-C₄₄H₃₂P₂—
CatalystPalladium (II) acetateC₄H₈O₄Pd—
Solvent1,4-DioxaneC₄H₈O₂—
Productcis-3,5-Dimethyl-1-[4-(methyloxy)-3-nitrophenyl]piperazineC₁₃H₁₉N₃O₃89.79%

The equation does not balance as written. That is usual for an experimental record: the source listed what it put in and what it measured, not a stoichiometric equation.

Conditions

Temperature
100 °C

Only the dimensions the source stated are listed. Anything absent here was not recorded, and it is not inferred from what the class usually needs.

Yield

  • 90% of cis-3,5-Dimethyl-1-[4-(methyloxy)-3-nitrophenyl]piperazine.

Procedure

Copied from the source record, unedited

To a solution of 4-bromo-1-methoxy-2-nitrobenzene (1500 mg, 6.46 mmol) in dioxane (40 mL) was added (2R,6S)-2,6-dimethylpiperazine (2215 mg, 19.39 mmol) followed by cesium carbonate (3159 mg, 9.70 mmol), 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (564 mg, 0.91 mmol) and diacetoxypalladium (145 mg, 0.65 mmol). The resulting mixture was heated at 100 °C under argon over night (black). LCMS Ok. The solids were filtered through celite and washed with ethyl acetate. The ethyl acetate was evaporated under reduced pressure and the crude product was purified by flash- chromatograpy eluated with Dichloromethane/ 2 M NH3 in Methanol 100/0 =>80/20 over 20 min. The pure fractions was collected and concentrated to give (3R,5S)-1-(4-methoxy-3-nitrophenyl)-3,5-dimethylpiperazine (1540 mg, 90 %) as red s

The source

This record comes from experimental reaction archive (ord-5dbc6ee86ad94d33b87d1fb77112c522). Open the source and check it against what is on this page.

  • experimental reaction archive record ord-5dbc6ee86ad94d33b87d1fb77112c522 from dataset "750 AstraZeneca ELN dataset" (url: https://chemrxiv.org/engage/chemrxiv/article-details/60c9e3f37792a23bfdb2d471). No atom mapping is provided by the source.

    experimental record · quality medium · source

experimental reaction record.

How to read this record

This is one experiment, not a rule. It says that on one occasion these species were combined under these conditions and this came out. It does not say the reaction will give the same result on your substrate, and nothing on the page has been generalised into a claim that it would.

The pathway is a separate question, kept on separate pages. A mechanism here is the canonical arrow pushing for a class, run on real structures and labelled rule-derived. It is not evidence, and this record is not a mechanism.