13795-02-3

Basic information

• Product Name: 3-(tert-butyl)-1-phenyl-1H-pyrazole-4,5-dione
• Synonyms: 3-(tert-butyl)-1-phenyl-1H-pyrazole-4,5-dione
• CAS NO: 13795-02-3
• Molecular Weight: 230.266
• Mol File: 13795-02-3.mol
• Article Data: 5

Chemical Properties

• CAS DataBase Reference: 3-(tert-butyl)-1-phenyl-1H-pyrazole-4,5-dione(CAS DataBase Reference)
• NIST Chemistry Reference: 3-(tert-butyl)-1-phenyl-1H-pyrazole-4,5-dione(13795-02-3)
• EPA Substance Registry System: 3-(tert-butyl)-1-phenyl-1H-pyrazole-4,5-dione(13795-02-3)

Safety Data

• Hazardous Substances Data: 13795-02-3(Hazardous Substances Data)

Upstream product

• 59-88-1 phenylhydrazine hydrochloride 
• 17094-34-7 ethyl pivaloylacetate 
• 6631-89-6 5-(tert-butyl)-2-phenyl-2,4-dihydro-3H-pyrazol-3-one 

Relevant articles and documents

Asymmetric Organocatalytic Friedel-Crafts Hydroxyalkylation of Indoles Using Electrophilic Pyrazole-4,5-diones

The electrophilic reactivity of a series of novel pyrazole-4,5-dione derivatives in the organocatalytic Friedel-Crafts reaction with various substituted indoles has been tested. The disclosed procedure catalyzed by a cinchona alkaloid derivative allows the conjugation of two very important aza-heterocyclic scaffolds to generate a new class of indolylpyrazolones bearing a tetrasubstituted stereocenter in excellent yields (up to 99%) and with enantioselectivities of up to 94:6 er.

Squaramide-Catalyzed Asymmetric aza-Friedel–Crafts/N,O-Acetalization Domino Reactions Between 2-Naphthols and Pyrazolinone Ketimines

N-Boc ketimines derived from pyrazolin-5-ones were explored to develop an unprecedented domino aza-Friedel–Crafts/N,O-acetalization reaction with 2-naphthols. The novel method requires a catalyst loading of only 0.5 mol % of a bifunctional squaramide catalyst, is scalable to gram amounts, and provides a new series of furanonaphthopyrazolidinone derivatives bearing two vicinal tetra-substituted stereogenic centers in excellent yields (95–98 %) and stereoselectivity (>99:1 d.r. and 97–98 % ee). A different reactivity was observed in the case of 1-naphthols and other electron-rich phenols, which led to the aza-Friedel–Crafts adducts in 70–98 % yield and 47–98 % ee.

Organocatalytic Direct Asymmetric Indolization from Anilines by Enantioselective [3 + 2] Annulation

We report the efficient syntheses of chiral tetrahydroindole pyrazolinones by the asymmetric [3 + 2] cascade cyclizations (indolizations) of simple aniline derivatives with pyrazolinone ketimines as 2C synthons. The chiral phosphoric-acid-catalyzed system uses a concerted π-πinteraction/dual H-bond control strategy to catalytically direct the asymmetric aniline, which undergoes a highly chemo-, regio-, and enantioselective [3 + 2] cascade annulation, furnishing a series of optically active tetra-hydroindole pyrazolinones with two contiguous chiral aza-quaternary carbon centers in excellent yields with excellent enantioselectivities. This method features a relatively broad substrate scope for amines and 2-naphthylamines and highlights the emerging value of direct chiral indolizations from simple amine sources in organic synthesis.