21568-04-7

Upstream product

• 56164-78-4 1-naphthyl 3-methyl-2-butenoate 
• 90-15-3 α-naphthol 
• 3350-78-5 3,3-Dimethylacryloyl chloride 
• 711-79-5 1-hydroxy-2-acetonaphthone 
• 67-64-1 acetone 
• 105417-14-9 2-(1-hydroxynaphthyl) isobutenyl ketone 

Downstream Products

• 21568-15-0 2,2-dimethyl-2,3-dihydro-benzo[h]chromen-4-one-(2,4-dinitro-phenylhydrazone) 
• 16274-33-2 3,4-dihydro-2,2-dimethyl-2H-naphtho[1,2-b]-pyran 

Relevant academic research and scientific papers

Formation of 2,2-dimethylchroman-4-ones during the photoinduced rearrangement of some aryl 3-methyl-2-butenoate esters. A mechanistic insight

Several aryl 3-methyl-2-butenoate esters upon irradiation lead to the formation of [1,3]-migrated photoproducts, phenol and, surprisingly 2,2-dimethylchroman-4-one derivatives. The starting photochemical reaction takes place from the singlet excited state of the ester and as a total mechanism two consecutive reaction pathways are proposed. The former involves the photo-Fries rearrangement of the esters in all the solvents studied and, depending on the proticity of the solvent, the latter involves an ESIPT process followed by thermal 6π-electrocyclic reaction and/or thermal (intramolecular oxa-Michael addition) cyclization of the ortho regioisomers photoformed. This second pathway is responsible of the formation of the 2,2-dimethylchroman-4-one derivatives.

A mild and convenient one-pot photochemical synthesis of chroman-4-one derivatives. the photo-Fries rearrangement of (hetero)aryl 3-methyl-2-butenoate esters under basic catalysis

The biphasic base catalysis-mediated photo-Fries rearrangement reaction of aryl 3-methy-2-butenoate esters in room temperature cyclohexane - 10% KOH system was investigated. This mild photochemical reaction leads to the formation of chroman-4-one derivatives in good to high yield and in short reaction times (30-120 min) in a one-pot photochemical reaction. Also, the photochemical reaction, as a convenient, versatile, and general method, applies efficiently to polycyclic and heterocyclic 3-methy-2-butenaote esters.

Convenient Syntheses of Naturally Occurring Angular and Linear Naphthopvrans

A convenient synthesis of naturally occurring angular naphthopyrans and their 6-demethoxy derivatives is described starting from 2-acetyl-1-naphthols along with the synthesis of linear naphthopyrans from 3-acetyl-2-naphthol.