Two new syntheses of a 4-aminopyrazole: Condensation of an N-substituted vinamidinium salt with a functionalized hydrazine

Synthesis

Volumn , Issue 11, 2007, Pages 1697-1701

  Hill, George B ^a   Mortlock, Andrew A ^a  

^a ASTRAZENECA   (United Kingdom)

Author keywords

Buchwald coupling; Condensation; Heterocycles; Pyrazoles; Vinamidinium

Indexed keywords

BUCHWALD COUPLING; BUILDING BLOCK; HETEROCYCLES; PYRAZOLES; VINAMIDINIUM;

AMINATION; CONDENSATION REACTIONS; HYDRAZINE; SALTS; SYNTHESIS (CHEMICAL);

ORGANIC COMPOUNDS;

2 (4 AMINO 1H PYRAZOL 1 YL) N (2,3 DIFLUOROPHENYL)ACETAMIDE; 4 AMINOPYRAZOLE; ACETAMIDE DERIVATIVE; DIHEXAFLUOROPHOSPHATE; FLUOROPHOSPHATE; HYDRAZINE; PYRAZOLE DERIVATIVE; UNCLASSIFIED DRUG;

AMINATION; ARTICLE; POLYMERIZATION; SYNTHESIS;

EID: 34250342161     PISSN: 00397881     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-2007-966054     Document Type: Article

References (14)

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11. (a) Dousson , C. B.; Heron , N. M.; Hill, G. B. Synthesis 2005, 1817.
12. (b) Note: the dihexafluorophosphate salt 8 (used to prepare 6) is now supplied commercially by Acros and Kanto under the name of 'aminoreductone precursor'. The commercial product is listed as a tautomer of 8, but matches in its condensation chemistry that of the material previously described by us (Paul Warwick, personal communication)
13. Denni-Dischert, D.; Marterer, W.; Bänziger, M.; Yusuff, N.; Batt, D.; Ramsey, T.; Geng, P.; Michael, W.; Wang, R.-M. B.; Taplin, F.; Versace, R.; Cesarz, D.; Perez, L. B. Org. Process Res. Dev. 2006, 10, 70.
14. Hill, G. B. WO Patent WO2007034183, 2007; Chem. Abstr. 2007, 350598.