958883-15-3

Upstream product

• 87-41-2 2-benzofuran-1(3H)-one 
• 2216-51-5 (-)-menthol 
• 850848-05-4 2-(prenyloxymethyl)benzoic acid 
• 93612-81-8 tetra-n-butylammonium 2-(hydroxymethyl)benzoate 
• 870-63-3 prenyl bromide 

Downstream Products

• 298712-28-4 (1R,2S,5R)-5-methyl-2-(methylethyl)cyclohexyl-2-(hydroxymethyl)benzoate 
• 2216-51-5 (-)-menthol 

Relevant academic research and scientific papers

2-(Prenyloxymethyl)benzoyl (POMB) group: a new temporary protecting group removable by intramolecular cyclization

2-(Prenyloxymethyl)benzoates can be prepared from alcohols and readily available 2-(prenyloxymethyl)benzoic acid by standard acylation techniques or by Mitsunobu reaction with inversion of configuration. The POMB group can be cleaved first by oxidative removal of the prenyl group with DDQ followed by lactonization with expulsion of the alcohol catalyzed by Yb(OTf)3. These reaction conditions are compatible with the presence of a large number of common protecting groups.

2-(Prenyloxymethyl)benzoyl (POMB) as a new temporary protecting group for alcohols

The 2-(prenyloxymethyl)benzoyl (POMB) group was introduced in high yields to hydroxyl functions using the crystalline reagent, 2-(prenyloxymethyl)benzoic acid, in the presence of dicyclohexylcarbodiimide (DCC) and 4- dimethylaminopyridine (DMAP). 2-(Prenyloxymethyl)benzoic acid is readily available, in two steps, from phthalide in 65% overall yield. The POMB group can be cleaved, in two steps, by treatment with 2,3-dichloro-5,6-dicyanoquinone (DDQ) followed by intramolecular lactonisation of the resulting hydroxy ester induced by a catalytic amount of Yb(OTf)3·H2O. The reaction conditions are compatible with the presence of a number of protecting groups such as isopropylidene, benzyl, acetyl, chloroacetyl, benzoyl, levulinoyl, Fmoc and Boc groups.