Tin tetrachloride → 2-Allyl-4-(5-hexynoyl)-6-t-butylphenol

Participants

Reaction Conditions

Reaction Steps

A solution of 2-allyl-6-t-butylphenol (0.57 g; 3 mmol) in dry CH2Cl2 (12 ml) is cooled to -78° C., and 5-hexynoyl chloride (0.43 g; 3.3 mmol) is added via syringe, followed by SnCl4 (0.375 ml) added dropwise via syringe, with stirring under Argon. After 30 min the reaction is allowed to warm to 0° C. and is stirred at that temperature for 5 min; it is then quenched with ca 1 ml of 3N HCl. The reaction is poured into 100 ml water and extracted with 3×50 ml portions of ether. The combined ether layers are washed with 150 ml portions of water until the aqueous layer is neutral (pH test). The ether layer is dried (MgSO4), filtered, and concentrated in vacuo to give crude product, which is chromatographed with 20:1 hexane/EtOAc, giving 0.64 g 2-allyl-4-(5-hexynoyl)-6-t-butylphenol (77% yield). The product is recrystallized from hexane at 0° C. to give crystals melting at 62°-63° C.

Provenance & Evidence