Reactions of Piperidines

Reactions of Piperidines

Piperidine and pyrrolidine exhibit enhanced nucleophilic properties compared to diethylamine primarily due to reduced steric hindrance around the lone pair. In these heterocycles, the two alkyl substituents, which are the carbon atoms in the ring, are tightly positioned away from the nitrogen lone pair. Consequently, the approach of an electrophile becomes easier than in diethylamine, where the rotations of C-N and C-C bonds cause interference. The pKaH values of piperidine (11.29) and pyrrolidine (11.27) are characteristic of amine bases, indicating that they are slightly stronger bases than diethylamine (10.98).

Reacion-1:

Cross-coupling processes can employ enol phosphates that originate from N-acyl-piperidin-2-one.

Related Products:

Reacion-2:

Hofmann exhaustive methylation:

Related Products:

See also:

References:

[1]Blackburne I D, Katritzky A R, Takeuchi Y. Conformation of piperidine and of derivatives with additional ring hetero atoms[J]. Accounts of Chemical Research, 1975, 8(9): 300-306.

[2]Katritzky A R, Patel R C, Riddell F G. N‐Methyl Inversion Barriers in Six‐membered Rings[J]. Angewandte Chemie International Edition in English, 1981, 20(6‐7): 521-529.

[3]Lepifre F, Clavier S, Bouyssou P, et al. Palladium-catalyzed coupling of vinyl phosphates with aryl or heteroaryl boronic acids. Application to the synthesis of substituted nitrogen containing heterocycles[J]. Tetrahedron, 2001, 57(32): 6969-6975.