155095-23-1

Basic information

• Product Name: 2H-Indazole, 4,5,6,7-tetrahydro-4-methyl-7-(1-methylethyl)-2-(1-oxopropyl)-3-phenyl-, (4R,7S)-
• CAS NO: 155095-23-1
• Molecular Formula: C20H26N2O
• Molecular Weight: 310.439
• Mol File: 155095-23-1.mol

Chemical Properties

• CAS DataBase Reference: 2H-Indazole, 4,5,6,7-tetrahydro-4-methyl-7-(1-methylethyl)-2-(1-oxopropyl)-3-phenyl-, (4R,7S)-(CAS DataBase Reference)
• NIST Chemistry Reference: 2H-Indazole, 4,5,6,7-tetrahydro-4-methyl-7-(1-methylethyl)-2-(1-oxopropyl)-3-phenyl-, (4R,7S)-(155095-23-1)
• EPA Substance Registry System: 2H-Indazole, 4,5,6,7-tetrahydro-4-methyl-7-(1-methylethyl)-2-(1-oxopropyl)-3-phenyl-, (4R,7S)-(155095-23-1)

Safety Data

• Hazardous Substances Data: 155095-23-1(Hazardous Substances Data)

Upstream product

• 98-88-4 benzoyl chloride 
• 155095-12-8 (3R,6S)-2-Benzoyl-3-methyl-6-isopropylcyclohexanone 
• 79-03-8 propionyl chloride 
• 155095-10-6 (4R,7S)-3-phenyl-4-methyl-7-isopropyl-4,5,6,7-tetrahydro-1H-indazole 

Downstream Products

• 1445-91-6 (S)-1-phenylethanol 
• 1517-69-7 (R)-1-phenylethanol 
• 107832-32-6 (R)-1-phenylethyl propionate 
• 120-45-6 (S)-1-phenylethyl propionate 
• 331991-67-4 methyl 3-methyl-4-oxo-4-(3-phenyl-l-menthopyrazol-2-yl)butanoate 
• 164913-54-6 (2R,3S)-(-)-2-methyl-3-(4-methylphenylsulfonamido)-3-phenylpropanoic acid 
• 193980-00-6 (2R,3R)-(+)-2-methyl-3-(4-methylphenylsulfonamido)-3-phenylpropanoic acid 

Relevant articles and documents

Resolution of secondary alcohols using 2-acyl-3-phenyl-l-menthopyrazoles as enantioselective acylating agents

The chelation of AlCl3 with N-acylpyrazoles leads to structural fixation of the acyl moiety and an acceleration in the rate of acylation of secondary alcohols. The chiral environment of the fixed acyl moiety of 2-acyl-3-phenyl-l-menthopyrazole 2 causes diastereofacial selectivity in the reaction with secondary alcohols, and thus 2 behaves as an enantioselective acylating agent. By the use of 2.4 molar equivalents of racemic 1-phenylethanol 3a, 2-acetyl-3-phenyl-l-menthopyrazole 2a afforded (S)-1-phenylethyl acetate (S)-4aa enantioselectively and unreacted 3a was recovered with (R)-configuration. Furthermore, the inverse configurational preferences were observed to give (R)-4aa and (S)-3a by the addition of strongly basic amines, which sometimes behaved as catalysts for enolate formation from 2 and AlCl3. These dramatic changes in stereoselective preference should be useful properties of 2-acyl-3-phenyl-l-menthopyrazole 2 as an enantioselective acylating agent.

Diastereoselective α-alkylation of 2-acyl-3-phenyl-l-menthopyrazoles

N-Acylpyrazoles were α-alkylated in good yields by the treatment with alkyl halides after metalation with LDA or LiHMDS. In the case of chiral N-acylpyrazoles, e.g., 2-acyl-3-phenyl-l-menthopyrazoles (4), the α-alkylation was highly diastereoselective. The subsequent α-alkylation products could be converted into esters in good yield in the presence of BF3·OEt2 without the loss of the optical purity.

Stereoselective N-acylation of a new chiral auxiliary compound; 3-phenyl-l-menthopyrazole

As a new chiral auxiliary compound having a pyrazole ring system, the synthetic utility of (4R,7S)-3-phenyl-4-methyl-7-isopropyl-4,5,6,7-tetrahydroindazole (3-phenyl-l-menthopyrazole), which was prepared from l-menthone, was discussed.