Réaction #51265

Équation de réaction

3-(4,4-dimethylchroman-8-yl)-1-propyne

methyl 2-hydroxy-4-iodobenzoate

→

Methyl 2-hydroxy-4-[3-(4,4-dimethylchroman-8-yl)-prop-1-ynyl]benzoate

Solvants

triethylamine

Conditions de réaction

Traitement

1. 1
   AutreThe reaction mixture is degassed
2. 2
   workup.ADDITIONare introduced
3. 3
   AutreThe reaction mixture is evaporated to dryness
4. 4
   Autrehydrochloric acid (1N), and the organic phase is separated
5. 5
   Séchagedried over magnesium sulphate
6. 6
   Autreevaporated
7. 7
   AutreThe residue is purified by chromatography on a silica column
8. 8
   Lavageeluted with heptane
9. 9
   AutreAfter evaporating the solvents
10. 10
    Autrean oil, which slowly crystallizes
11. 11
    Autreis obtained
12. 12
    Autreis recrystallized from heptane
13. 13
    Autre1.00 g (50%) of methyl 2-hydroxy-4-[3-(4,4-dimethylchroman-8-yl)prop-1-ynyl]benzoate is collected in the form of a white solid with a melting point of 92-93° C.

Mode opératoire

1.18 g (5.9 mmol) of 3-(4,4-dimethylchroman-8-yl)-1-propyne, 1.60 g (5.9 mmol) of methyl 2-hydroxy-4-iodobenzoate and 60 ml of triethylamine are introduced into a three-necked flask under argon. The reaction mixture is degassed by sparging with nitrogen, 332 mg (0.46 mmol) of bis(triphenylphosphine) palladium(II) chloride and 134 mg of copper iodide are introduced and the mixture is stirred at room temperature for eight hours. The reaction mixture is evaporated to dryness, the residue is taken up in ethyl acetate and hydrochloric acid (1N), and the organic phase is separated by settling, dried over magnesium sulphate and evaporated. The residue is purified by chromatography on a silica column eluted with heptane. After evaporating the solvents, an oil, which slowly crystallizes, is obtained and is recrystallized from heptane. 1.00 g (50%) of methyl 2-hydroxy-4-[3-(4,4-dimethylchroman-8-yl)prop-1-ynyl]benzoate is collected in the form of a white solid with a melting point of 92-93° C.

Source