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Buchwald–Hartwig amination: 5-Chloro-2-nitroanisole → Tert-butyl 4-(3-methoxy-4-nitrophenyl)-3-oxopiperazine-1-carboxylate

100% yield, run at 90 °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, 100% 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

COCCCNCCNCOOCCCCCCOCCCNOOCl
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
Reactant5-Chloro-2-nitroanisoleC₇H₆ClNO₃—
ReactantTert-butyl 3-oxopiperazine-1-carboxylateC₉H₁₆N₂O₃—
ReagentCesium carbonateCCs₂O₃—
Catalyst1,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine)C₃₉H₃₂OP₂—
CatalystBis(dibenzylideneacetone)palladiumC₅₁H₄₂O₃Pd₂—
Solvent1,4-DioxaneC₄H₈O₂—
ProductTert-butyl 4-(3-methoxy-4-nitrophenyl)-3-oxopiperazine-1-carboxylateC₁₆H₂₁N₃O₆100.3%

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
90 °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

  • 100% of Tert-butyl 4-(3-methoxy-4-nitrophenyl)-3-oxopiperazine-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
1,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine); Bis(dibenzylideneacetone)palladiumCesium carbonate1,4-Dioxane90 °C—100% (this run)
1,1'-(9,9-Dimethyl-9H-xanthene-4,5-diyl)bis(1,1-diphenylphosphine); Palladium (II) acetateCesium carbonate1,4-Dioxane90 °C—68%

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

A mixture of tert-butyl 3-oxopiperazine-1-carboxylate (1500 mg, 7.49 mmol), 4-chloro-2-methoxy-1-nitrobenzene (1405 mg, 7.49 mmol),cesium carbonate (3417 mg, 10.49 mmol), (9,9-dimethyl-9H-xanthene-4,5-diyl)bis(diphenylphosphine) (195 mg, 0.34 mmol) and TRIS(DIBENZYLIDENEACETONE)DIPALLADIUM (174 mg, 0.19 mmol)was dried for 15 min under HV. Degassed dioxane (17 ml) was added and the resulting mixture was stirred at 90°C for 16 hours under inert atmosphere. Work-up and purification: see EN02378-07-02. tert-butyl 4-(3-methoxy-4-nitrophenyl)-3-oxopiperazine-1-carboxylate (2640 mg, 100 %) was isolated as an orange foam. FLA 02378-10-01: 1H NMR, LC-MS: OK.

The source

This record comes from experimental reaction archive (ord-ba7ec5906e7d4fb89a5c2ef7e7a905ac). Open the source and check it against what is on this page.

  • experimental reaction archive record ord-ba7ec5906e7d4fb89a5c2ef7e7a905ac 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.