5932-31-0 | 1,4,5,6-Tetrahydro-cyclopentapyrazole-3-carboxylic acid ethyl ester

Packsize	Purity	Availability	Price	Discounted Price
1g	97%	in stock	$47.00	$33.00
5g	97%	in stock	$127.00	$89.00

Description

• Catalog Number: AG68896
• Chemical Name: 1,4,5,6-Tetrahydro-cyclopentapyrazole-3-carboxylic acid ethyl ester
• CAS Number: 5932-31-0
• Molecular Formula: C9H12N2O2
• Molecular Weight: 180.20378000000002
• MDL Number: MFCD07778361
• SMILES: CCOC(=O)c1n[nH]c2c1CCC2

Computed Properties

• Complexity: 208
• Covalently-Bonded Unit Count: 1
• Heavy Atom Count: 13
• Hydrogen Bond Acceptor Count: 3
• Hydrogen Bond Donor Count: 1
• Rotatable Bond Count: 3
• XLogP3: 1.5

Upstream Synthesis Route

The synthesis of 1,4,5,6-Tetrahydro-cyclopentapyrazole-3-carboxylic acid ethyl ester requires the preparation of the cyclopentapyrazole core followed by subsequent esterification. The starting materials for constructing the pyrazole ring are typically a 1,3-dicarbonyl compound and a hydrazine.

1. Start with ethyl acetoacetate and hydrazine to form an ethyl pyrazole-3-carboxylate through a series of condensation and cyclization steps.

2. Perform a Michael addition of a nucleophile, such as nitromethane, to introduce the nitro group adjacent to the pyrazole ring. This adds one carbon to the ring and will be useful in the later reduction and cyclization steps.

3. Conduct reduction of the nitro group to the corresponding amine with a reducing agent like palladium on carbon (Pd/C) under a hydrogen atmosphere.

4. Close the cyclopentane ring by reacting the amine with a suitable β-keto ester or β-dicarbonyl, depending on the number of methylene groups required, through a reductive amination or similar cyclization process.

5. Finally, perform hydrogenation to reduce the pyrazole ring to tetrahydrocyclopentapyrazole.

6. The resulting tetrahydropyrazole compound could be esterified using ethanol in the presence of a strong acid like sulfuric acid to yield the desired ethyl ester.

Please note that each step may require optimizations in terms of solvents, reaction conditions, and purification techniques to achieve the desired product with high yield and purity. Additionally, each intermediate must be characterized, usually by NMR, IR, and MS, to ensure the correct structure before proceeding to the next step.