1,5-Diazabicyclo(4.3.0)non-5-ene

1,5-Diazabicyclo(4.3.0)non-5-ene (often abbreviated as DBN) is a chemical compound classified as an amidine. It is a colorless solid that is used as a catalyst in organic synthesis.

Structure and Bonding

DBN is a bicyclic structure, which means it consists of two fused cyclic compounds. The molecule is composed of a six-membered ring and a three-membered ring, with two nitrogen atoms at the 1 and 5 positions of the six-membered ring. The bicyclic structure of DBN is rigid, which contributes to its effectiveness as a catalyst.

Synthesis

DBN can be synthesized from 1,4-diaminobutane and malonic acid. The reaction involves the formation of an imine intermediate, followed by intramolecular cyclization and dehydration.

Applications

DBN is primarily used as a catalyst in organic synthesis. It is particularly effective for reactions that involve the formation of new carbon-nitrogen bonds, such as the Michael reaction and the aldol reaction. DBN is also used as a base in the synthesis of other organic compounds.

Safety

DBN is a strong base and can cause burns if it comes into contact with skin or eyes. It should be handled with care, using appropriate personal protective equipment.

See also

• [[1,8-Diazabicyclo[5.4.0]undec-7-ene]] (DBU)
• Organocatalysis
• Amidine