Continuous gas/liquid–liquid/liquid flow synthesis of 4-fluoropyrazole derivatives by selective direct fluorination

• Jessica R. Breen,
• Graham Sandford,
• Dmitrii S. Yufit,
• Judith A. K. Howard,
• Jonathan Fray and
• Bhairavi Patel

Beilstein J. Org. Chem. 2011, 7, 1048–1054, doi:10.3762/bjoc.7.120

• pyrazole derivatives [22][23]. Of relevance to this paper, pyrazole and its derivatives constitute an important class of compounds, which exhibit various biological and pharmaceutical activities ranging from antitumor to anti-inflammatory, antipsychotic, antimicrobial, antiviral and antifungal activities

Approaches towards the synthesis of 5-aminopyrazoles

• Ranjana Aggarwal,
• Vinod Kumar,
• Rajiv Kumar and
• Shiv P. Singh

Beilstein J. Org. Chem. 2011, 7, 179–197, doi:10.3762/bjoc.7.25

• herein report a detailed account of the synthetic methods available for 5-aminopyrazoles. As pyrazole derivatives do not exist in nature, probably, due to the difficulty in the construction of N–N bond by living organisms, their availability depends on the synthetic methods. A large number of synthetic

• chloride, which affords, again after Fmoc removal, the diglycylpyrazole 142 (Scheme 38) [80]. A new synthetic route [81] to 5-amino-1-aryl-4-benzoyl pyrazole derivatives 144 involves the reaction of β-ketonitriles with N,N’-diphenylformamidine to give initially the cyclocondensation precursors 143 which is

Michael-type addition of azoles of broad-scale acidity to methyl acrylate

• Sławomir Boncel,
• Kinga Saletra,
• Barbara Hefczyc and
• Krzysztof Z. Walczak

Beilstein J. Org. Chem. 2011, 7, 173–178, doi:10.3762/bjoc.7.24

• , no corresponding regioisomers were obtained. Keywords: imidazole derivatives; methyl acrylate; Michael-type addition; pyrazole derivatives; 1,2,4-triazole derivatives; Introduction Derivatives of azoles are important biologically active compounds. Many, especially those containing imidazole