<i>trans</i>-Stilbene
as a Starting Material for the Synthesis of Tamoxifen Based on Palladium-Catalyzed
Cross-Coupling Reactions
作者:Adriano Monteiro、Carolina Nunes、Jones Limberger、Silvia Poersch、Marcus Seferin
DOI:10.1055/s-0029-1217600
日期:——
(Z)-Tamoxifen was synthesized from a simple olefin (trans-stilbene) in 5 steps and 40% overall yield (Z/E = 74:26). The phenyl substituted group (4-Me2NCH2CH2OC6H4) was attached by a bromination-dehydrobromination-Suzuki reaction sequence. Subsequently, the ethyl group was attached to the triarylated olefin by a bromination-Negishi reaction sequence. Both the Suzuki and Negishi cross-coupling processes are stereospecific, and the stereoselectivity depends only on the bromination-dehydrobromination reactions. (Z)-Tamoxifen was also obtained from trans-stilbene in only 3 steps by using Heck reaction-bromination-Negishi reaction sequence in 57% overall yield (Z/E = 65:35).
(Z)-他莫昔芬是由简单的烯烃(反式二苯乙烯)经 5 个步骤合成的,总收率为 40%(Z/E = 74:26)。苯取代基(4-Me2NCH2CH2OC6H4)是通过溴化-脱氢溴化-铃木反应顺序连接的。随后,通过溴化-内吉西反应序列将乙基连接到三芳基化烯烃上。铃木和根岸交叉偶联过程都是立体特异性的,而立体选择性只取决于溴化-脱氢溴化反应。(通过赫克反应-溴化-内箕反应顺序,仅用 3 个步骤就从反式二苯乙烯中得到了 (Z)-他莫昔芬,总收率为 57%(Z/E = 65:35)。