Mono S-trimethylsilyl ketene dithioacetals as versatile tools for the synthesis of α-hydrazinodithioesters. A novel access to endothiopeptides.
摘要:
Mono-S-trimethylsilylketene dithioacetals have been prepared from dithioesters by the action of trimethylsilyl iodide formed in situ. They were reacted easily with dialkylazodicarboxylates to give good yields of alpha-hydrazinodithioesters. The latter were transformed into thioamides or endothiodipeptides by aminolysis either with an amine or an amino acid.
reactions using a catalytic amount of tin(II) reagents have been developed. Namely, an aldol type reaction of tin(II) enolate is achieved starting from α,β-unsaturatedketone, aldehyde and ethylthiotrimethylsilane in the presence of a catalytic amount of tin(II) triflate sulfide. Furthermore, the catalyticasymmetric Michael reaction of tin(II) enethiolate is realized just by using a catalytic amount of tin(II)
The catalyticasymmetricMichaelreaction of tin(II) enethiolates forming 5-oxodithioesters in high yield with moderate to good enantioselectivity is achieved by employing catalytic amounts of stannous triflate and chiral diamine.
通过使用催化量的三氟甲磺酸亚锡和手性二胺,实现了锡 (II) 烯硫醇的催化不对称迈克尔反应,以高产率形成 5-氧代二硫酯,具有中等至良好的对映选择性。
Efficient Method for the Preparation of Vinylthio- and Vinylselenosilanes
作者:Ramesh S. Sukhai、Lambertus Brandsma
DOI:10.1055/s-1979-28717
日期:——
IWASAWA, NOBUHARU;YURA, TAKESHI;MUKAIYAMA, TERUAKI, TETRAHEDRON, 45,(1989) N, C. 1197-1207