Thermolysis of O-allyl S-alkyl dithiocarbonates of codeine and isocodeine.
作者:IKUO FUJII、MASAKO KOREYUKI、KEN KANEMATSU
DOI:10.1248/cpb.36.1750
日期:——
The reactions of O-allyl S-alkyl dithiocarbonates of codeine and isocodeine were examined under thermal and catalytic conditions. Heating of a xylene solution of xanthates (3, 4, and 5) gave the corresponding S-allyl S-alkyl dithiocarbonates (6, 7, and 8) via [3, 3] sigmatropic rearrangement in high yields, overcoming the difficulty of attack on the hindered α-face. On the other hand, in the case of isocodeine, the formation of xanthates followed by the rearrangement took place without heating to afford the dithiocarbonates (9, 10, and 11). Furthermore, compound 10 rearranged with extrusion of COS to give the sulfide (14). The reactions of 3, 6, and 9 with phosphine-palladium (0) complex and a Lewis acid as catalysts were also examined. When 3 or 6 was treated with (Ph3P)4Pd, elimination reaction proceeded to give 6-demethoxythebaine (17). The reactions of 6 and 9 with TiCl4 yielded the corresponding cyclic dithiocarbonates 18 and 19.
在热力学和催化条件下,考察了可待因和异可待因的O-烯丙基S-烷基二硫代碳酸盐的反应。将黄原酸盐(3、4和5)的二甲苯溶液加热,通过[3, 3]同位素重排反应高效地获得了相应的S-烯丙基S-烷基二硫代碳酸盐(6、7和8),克服了α-位阻面的进攻难题。另一方面,在异可待因的情况下,形成黄原酸盐后无需加热即可发生重排,生成二硫代碳酸盐(9、10和11)。此外,化合物10通过排出COS,重排生成了硫醚(14)。还考察了3、6和9与磷钯(0)配合物及Lewis酸作为催化剂的反应。当3或6与(Ph3P)4Pd反应时,发生了消除反应,生成6-去甲氧基蒂巴因(17)。6和9与TiCl4反应生成了相应的环状二硫代碳酸盐18和19。