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Buchwald–Hartwig amination: Benzonitrile, 4-bromo- → Tert-butyl 4-(4-cyanophenyl)piperazine-1-carboxylate

82% yield, run at 120 °C, as recorded by experimental reaction archive. The written procedure is below.

verified record, 82% 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

CCCCOCONCCNCCCCCNCCCCBr
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
ReactantBenzonitrile, 4-bromo-C₇H₄BrN—
Reactanttert-Butyl piperazine-1-carboxylateC₉H₁₈N₂O₂—
Reagentsodium 2-methylpropan-2-olateC₄H₉NaO—
Catalyst2-Dicyclohexylphosphino-2',4',6'-triisoprophylbiphenylC₃₃H₄₉P—
CatalystPalladium (II) acetateC₄H₈O₄Pd—
SolventTetrahydrofuranC₄H₈O—
ProductTert-butyl 4-(4-cyanophenyl)piperazine-1-carboxylateC₁₆H₂₁N₃O₂82.34%

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
120 °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

  • 82% of Tert-butyl 4-(4-cyanophenyl)piperazine-1-carboxylate.

Procedure

Copied from the source record, unedited

To 4-bromobenzonitrile (.5 g, 2.75 mmol) dissolved in dry THF (10 mL) was added tert-butyl piperazine-1-carboxylate (0.512 g, 2.75 mmol), Sodium-t- butoxide (0.792 g, 8.24 mmol) and purged with N2 gas for 10 min followed by the addition of 2-(Dicyclohexylphosphino)-2',4',6'-tri-i-propyl-1,1'-biphenyl (0.131 g, 0.27 mmol)and Palladium II acetate (0.062 g, 0.27 mmol). The contents were further purged with N2 gas for further 10 min and heated at 85 °C for 2 h. The reaction mass was concentrated and the reside diluted with water and extracted with ethyl acetate . The combined organic extracts were washed with brine solution and dried over anhydrous sodium sulphate. The organic layer was evaporated under reduced pressure to obtain the crude product which was purified by 60-120 mesh silica gel c

The source

This record comes from experimental reaction archive (ord-587e8b015ef542aa9ba95a064a0d6902). Open the source and check it against what is on this page.

  • experimental reaction archive record ord-587e8b015ef542aa9ba95a064a0d6902 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.