19854-91-2

Basic information

• Product Name: 5-(Hydroxyphenylmethyl)pyrazol
• Synonyms: 5-(Hydroxyphenylmethyl)pyrazol
• CAS NO: 19854-91-2
• Molecular Weight: 174.202
• Mol File: 19854-91-2.mol
• Article Data: 3

Chemical Properties

• CAS DataBase Reference: 5-(Hydroxyphenylmethyl)pyrazol(CAS DataBase Reference)
• NIST Chemistry Reference: 5-(Hydroxyphenylmethyl)pyrazol(19854-91-2)
• EPA Substance Registry System: 5-(Hydroxyphenylmethyl)pyrazol(19854-91-2)

Safety Data

• Hazardous Substances Data: 19854-91-2(Hazardous Substances Data)

Upstream product

• 133228-23-6 1-(Dimethylsulfamoyl)-5-pyrazol 
• 133228-24-7 1-(Dimethylsulfamoyl)-5-(hydroxyphenylmethyl)pyrazol 
• 1120-82-7 pyrazole-1-methanol 
• 100-52-7 benzaldehyde 
• 288-13-1 NH-pyrazole 

Relevant articles and documents

Formaldehyde: A Reagent for Simultaneous Protection of Heterocyclic NH and Activation of Alternative Locations to Electrophilic Attack. Part II. A New Synthetic Method for the 5(3)-Substitution of N-Unsubstituted Pyrazoles

N-Unsubstituted pyrazole 1 is readily converted into 5-substituted derivatives 2 in moderate to good overall yields in a one-pot sequence, using formaldehyde both for N-protection and to mediate lithiation at the 5-position.The dilithiohemiaminals 5 react with electrophiles at the pyrazole 5-position to give 5-substituted 1-lithioxymethylpyrazoles 6 which undergo smooth dehydroxymethylation under mild conditions (acid hydrolysis or silica gel) to give N-unsubstituted 5(3)-substituted pyrazoles.

Carbodesilylation of (Trimethylsilyl)imidazoles and -pyrazoles

The preparation of the 1-methyl(trimethylsilyl) (TMS)-substituted imidazoles 3a, 4a, 8, 9, and 11a by silylation of the corresponding metallated imidazoles is described.Carbodesilylation of 3 with aldehydes or carboxylic halogenides occurs selectively in 2-position.In the presence of a strong base (CsF) the reactivity against carbon electrophiles correlates well with the stability of the imidazolyl anions; regioselective carbodesilylation in 2-, 5-, or 4-position of the twofold TMS-substituted imidazoles 3a and 9 therefore is possible, which allows the synthesis of a great variety of hydroxyalkyl-substituted imidazoles and of acylimidazoles.By using the dimethylsulfamoyl substituent as an N-protecting group, the N-unsubstituted 5-benzoylimidazole (26) as well as the comparable 5-benzoyl-pyrazole (30b) and 5-(hydroxyphenylmethyl)pyrazole (30a) are accessible. Key Words : Imidazoles, (trimethylsilyl)-, carbodesilylation of / Pyrazoles, (trimethylsilyl)-, carbodesilylation of / Carbodesilylation