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Buchwald–Hartwig amination: 3-Bromopyridine → Tert-butyl 4-(pyridin-3-YL)piperazine-1-carboxylate

29% yield, run at 85 °C, as recorded by experimental reaction archive. The written procedure is below. One of 2 recorded runs making this product; all of them are compared below.

verified record, 29% 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

CCCCOCONCCNCCCCNCCCBr
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
Reactant3-BromopyridineC₅H₄BrN—
Reactanttert-Butyl piperazine-1-carboxylateC₉H₁₈N₂O₂—
Reagentsodium 2-methylpropan-2-olateC₄H₉NaO—
CatalystBinap, (A+-)-C₄₄H₃₂P₂—
CatalystBis(dibenzylideneacetone)palladiumC₅₁H₄₂O₃Pd₂—
SolventTolueneC₇H₈—
ProductTert-butyl 4-(pyridin-3-YL)piperazine-1-carboxylateC₁₄H₂₁N₃O₂29.23%

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
85 °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

  • 29% of Tert-butyl 4-(pyridin-3-YL)piperazine-1-carboxylate.

Every recorded run making this product

2 runs of this class made the same product and differed in what else was in the flask. They are listed from the highest yield down, with this page's run marked.

CatalystReagentsSolventTemp.TimeYield
2-Dicyclohexylphosphino-2',6'-diisopropoxybiphenyl; Palladium (II) acetatesodium 2-methylpropan-2-olate1,4-Dioxane100 °C—38%
Binap, (A+-)-; Bis(dibenzylideneacetone)palladiumsodium 2-methylpropan-2-olateToluene85 °C—29% (this run)

Every value is as the source recorded it. A run with no yield was reported without one, and nothing here is averaged, modelled or filled in.

Procedure

Copied from the source record, unedited

TRIS(DIBENZYLIDENEACETONE)DIPALLADIUM(0) (0.059 g, 0.06 mmol) and rac-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (0.080 g, 0.13 mmol) were mixed together and evacuated and purged with nitrogen 3 times. toluene (31.6 ml) was added and the resulting mixture heated to 90°C for 10 minutes then cooled to room temperature. sodium tert-butoxide (0.465 g, 4.84 mmol), 3-bromopyridine (0.310 ml, 3.22 mmol) and tert-butyl piperazine-1-carboxylate (0.6 g, 3.22 mmol) were added and the resulting mixture was heated at 85 °C for 64 hours. The reaction mixture was cooled to RT and filtered through celite and concentrated to give an orange solid. The crude product was purified by flash silica chromatography, elution gradient 30 to 50% EtOAc in heptane. Pure fractions were evaporated to dryness to afford t

The source

This record comes from experimental reaction archive (ord-7977e1a392644e76ab21a7fab838843f). Open the source and check it against what is on this page.

  • experimental reaction archive record ord-7977e1a392644e76ab21a7fab838843f 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.