Rearrangement of the Angular Methyl Group in Dehydroabietic Acid Derivatives.
作者:Takashi MATSUMOTO、Yasutaka TANAKA、Hiromitsu TERAO、Yoshio TAKEDA、Makoto WADA
DOI:10.1248/cpb.41.1960
日期:——
The rearrangement of the angular methyl group in dehydroabietic acid derivatives was examined. Treatment of 12-methoxy-5, 8, 11, 13-abietatetraene (25) with boron trifluoride etherate afforded 12-methoxy-5β-methyl-10-norabieta-1(10), 8, 11, 13-tetraene (26). On the other hand, 12-methoxy-7-oxo-5, 8, 11, 13-abietatetraene (27) provided three naphthalene derivatives, 28, 29 and 30, on treatment with sulfuric acid in acetic anhydride. Methyl 7-oxo-5, 8, 11, 13-abietatetraen-18-oate (5) was reduced with sodium borohydride in the presence of cerium(III) chloride heptahydrate and the resulting alcohol (32) was further treated with p-toluensulfonic acid monohydrate to give methyl 5β-methyl-10-norabieta-1(10), 6, 8, 11, 13-pentaen-18-oate (33). On the other hand, under similar conditions, 7-oxo-5, 8, 11, 13-abietatetraene (11) and its 12-methoxy derivative (27) were transformed into the naphthalene derivatives, 35 and 37, respectively, via the corresponding alcohols, 34 and 36.
研究了脱氢松香酸衍生物中角甲基的重排。用三氟化硼醚化物处理 12-甲氧基-5,8,11,13-阿松香四烯(25),可得到 12-甲氧基-5β-甲基-10-去甲松香-1(10),8,11,13-四烯(26)。另一方面,12-甲氧基-7-氧代-5、8、11、13-阿比埃塔四烯(27)在乙酸酐中用硫酸处理后,可得到三种萘衍生物 28、29 和 30。在七水合氯化铈(III)存在下,用硼氢化钠还原 7-氧代-5,8,11,13-联四烯-18-酸甲酯(5),得到的醇(32)进一步用对甲苯磺酸一水合物处理,得到 5β-甲基-10-去甲联四烯-1(10),6,8,11,13-戊烯-18-酸甲酯(33)。另一方面,在类似条件下,7-氧代-5,8,11,13-阿比特四烯(11)及其 12-甲氧基衍生物(27)通过相应的醇 34 和 36 分别转化为萘衍生物 35 和 37。