Abstract

Edy Cahyono¹, Sigit Priatmoko and Sri Haryani

DOI : http://dx.doi.org/10.13005/ojc/31.Special-Issue1.09

Regioselective acetylation of 2-methoxy naphthalene (2-MN) to 2-acetyl-6-methoxy naphthalene (2,6-ACMN) is the important step in the synthesis of pharmaceutical compounds such as (S)-naproxen. The liquid phase acetylation of 2-MN with acetic anhydride over Zr⁴⁺-zeolite beta catalyst was investigated under controlled reaction conditions. Catalyst was prepared by ion exchange and impregnation method. Zr⁴⁺-zeolite beta(ie) was obtained by ion exchange that done with 0,5 M ZrCl₄  then calcined at 550 ^oC for 3 h and Zr⁴⁺-zeolite beta(ip) was obtained by impregnation method. Catalytic activity of catalysts was affected by preparing method, temperature, and reaction solvent. Catalyst that prepared by impregnation showed inactive on acetylation of 2-MN. 1-Acetyl-2-methoxynaphtalene (1,2-ACMN), 1-acetyl-7-methoxy-naphtalene (1,7-ACMN), and 2-acetyl-6-methoxy naphthalene (2,6-ACMN) were identified as the products of 2-MN acetylation over Zr⁴⁺-zeolite beta(ie) without solvent. Activity and selectivity of Zr⁴⁺-zeolite beta(ie) was increased in dichloromethane solvent at 140^oC for 36 h, 1,8-ACMN was not identified and ratio of 1,2-ACMN to 2,6-ACMN was 1,6:1

Acetylation; 2-Acetyl-6-methoxynaphthalene; Zeolite beta; Regioselectivity; Solvent effect

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