What does DMAP do in a reaction?

What does DMAP do in a reaction?

DMAP is an acyl transfer reagent that reacts regioselectively at the less hindered carbonyl site: DMAP is a stronger nucleophile than the alcohol. The newly formed intermediate is less hindered, the acyl group is still polarized and DMAP is a good leaving group, all of which enable a fast reaction with the alcohol.

How does DMAP work as a catalyst?

DMAP (13) causes acylation rates to increase by factors as large as 10,000 when compared to reactions catalyzed by pyridine. A better explanation for DMAP being such an effective catalyst is that it reacts with acid chlorides, such as 12, to form high concentrations of N‑acylpyridinium salts (eq 7).

Is DMAP nucleophilic?

Because of its basicity, DMAP is a useful nucleophilic catalyst for a variety of reactions such as esterifications with anhydrides, the Baylis-Hillman reaction, hydrosilylations, tritylation, the Steglich rearrangement, Staudinger synthesis of β-lactams and many more.

Why is DMAP nucleophilic?

DMAP is an acyl-transfer agent. The nitrogen atom in the ring is a particularly good nucleophile, and it gets acylated quite rapidly. Because the resulting acyl pyridinium ion is a cation, the acyl pyridinium also releases DMAP as a good leaving group in subsequent acylation reactions.

What is the expected role of DMAP in the reaction?

What is the expected role of DMAP in the reaction? DMAP is used as a catalyst in acylation reactions as it acts via a nucleophilic addition mechanism [34,37,40].

What is the DMAP?

The Deer Management Assistance Program, (DMAP) is a comprehensive deer management program, consisting of data collection and cooperator education. Using this, the MDWFP tries to put the landowner/cooperator in a better position to manage their lands for a healthy deer herd, while maintaining habitat integrity.

Why is DMAP more basic than pyridine?

In DMAP, protonation on the pyridine ring nitrogen forms a structure that can gain stabilization through resonance. Through resonance, the nonbonding electron pair of the 4-dimethylamino group in protonated DMAP helps stabilize the positive charge, making DMAP a stronger base than pyridine itself.

Why is DMAP more nucleophilic than pyridine?

Why is DMAP a good base?

What is the role of DMAP?

The role of DMAP is to accelerate the acylation reaction by forming an N-C=O. bond (DMAP reacts with anhydride); hence, without it, you can use any other tertiary nitrogen base but expect a differentiated reaction rate relative to the use of DMAP.

What is the pKa of DMAP?


Melting point 112 °C
form prilled
pka pKa (20°): 9.7
color off-white to yellow
Odor characteristic odor

Is DMAP water soluble?

SOLUBILITY: Soluble in methanol, benzene, ethyl acetate, chloroform, me- thylene chloride, acetone, and acetic acid. Less soluble in ether, diisopropyl ether, cyclohexane, hexane, and water.