68097-97-2

Upstream product

• 110-89-4 piperidine 
• 95-87-4 2,5-Dimethylphenol 
• 50-00-0 formaldehyd 
• 3275-13-6 1-(ethoxymethyl)piperidine 
• 880-09-1 di(N-piperidinyl)methane 
• 20276-55-5 N-methylenepiperidinium chloride 

Downstream Products

• 120983-09-7 6-(N-morpholinylmethyl)-2,5-dimethylphenol 
• 120983-10-0 4,6-bis(N-morpholinylmethyl)-2,5-dimethylphenol 
• 6630-03-1 6-(N,N-diethylaminomethyl)-2,5-dimethylphenol 
• 69286-57-3 4-(N,N-diethylaminomethyl)-2,5-dimethylphenol 
• 120983-08-6 4,6-bis(N,N-diethylaminomethyl)-2,5-dimethylphenol 
• 120983-11-1 6-(N-pyrrolidinylmethyl)-2,5-dimethylphenol 
• 120983-12-2 4,6-bis(N-pyrrolidinylmethyl)-2,5-dimethylphenol 

Relevant academic research and scientific papers

The activation of aminals and aminol ethers by sulfur dioxide and their reactions with electron rich aromatic compounds

Reactions of bis(dialkylamino)methanes and ethoxydialkylaminomethanes with nucleophilic aromatic heterocycles in the presence of sulfur dioxide result in the formation of the expected Mannich bases in good yields. Reactions of phenols are similarly activated by sulfur dioxide which lead to improved regioselectivity: in particular the reactions of 2,5-dimethylphenol result in the formation of 2-dialkylaminomethyl-3,6-dimethylphenol whereas reaction occurs at the I-position using the classical procedures.

THE EFFECT OF SULPHUR DIOXIDE ON THE MANNICH REACTIONS OF PHENOLS

Regioselectivity in the ortho-dialkylaminomethylation of phenols in greatest, for example in reactions of 2,5-dimethylphenol, when a mixture of the phenol and sulphur dioxide is allowed to stand for several hours before the addition of a bis-(dialkylamino)methane (aminal) or an alkoxydialkylaminomethane (aminol ether).