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Buchwald–Hartwig amination: 4-Bromo-2-nitrotoluene → 1-(4-Methyl-3-nitrophenyl)piperazine

39% yield, run at 110 °C, as recorded by experimental reaction archive. The written procedure is below.

verified record, 39% 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

CCCCCNCCNCCCCNOOBrHHHHHHHHHH
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-nitrotolueneC₇H₆BrNO₂—
ReactantPiperazineC₄H₁₀N₂—
ReagentCesium carbonateCCs₂O₃—
CatalystBinap, (A+-)-C₄₄H₃₂P₂—
CatalystPalladium (II) acetateC₄H₈O₄Pd—
SolventTolueneC₇H₈—
Product1-(4-Methyl-3-nitrophenyl)piperazineC₁₁H₁₅N₃O₂39.25%

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
110 °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

  • 39% of 1-(4-Methyl-3-nitrophenyl)piperazine.

Procedure

Copied from the source record, unedited

palladium(II) acetate (0.065 g, 0.29 mmol), BINAP (0.144 g, 0.23 mmol) and CS2CO3 (0.943 g, 2.89 mmol) were added to a mixture of 4-bromo-1-methyl-2-nitrobenzene (0.5 g, 2.31 mmol) and piperazine (1.623 g, 18.84 mmol) . The suspension were heated to 110 °C for 24 hours, LCMS showed product mass [M+1]: 222.1 at retension time RT=1.21 min (polar short purity method). Workup reaction by additional of water (10mL), extracted with EtOAc (3x20 mL), washed with brine, dried with Na2SO4, evaporated off solvent to give a residue, which was purified by isco chromatographer, eluting with 0-10% MeOH in DCM to give 1-(4-methyl-3-nitrophenyl)piperazine (0.201 g, 39.3 %) as a yellow solid.

The source

This record comes from experimental reaction archive (ord-7a7d88bb15974f808c2ac9e73fb46a04). Open the source and check it against what is on this page.

  • experimental reaction archive record ord-7a7d88bb15974f808c2ac9e73fb46a04 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.