在无溶剂条件下,三氟甲磺酸镓(III)催化环氧化物的开环可提供具有高区域选择性和化学选择性的β-羟基硫化物,产率高(84-97%)。另外,首次开发了在单一水中合成β-羟基亚砜的简单,有效且对环境无害的一锅法。通过H 2 O 2 -Ga(OTf)3系统的促进,该过程以高收率(81-94%)和高化学选择性提供了β-羟基亚砜,而没有检测到对β-羟基砜的过度氧化。反应后催化剂可以容易地回收并重新使用而没有明显的活性损失。
Alumina-supported Molybdenum (VI) Oxide: An Efficient and Recyclable Heterogeneous Catalyst for Regioselective Ring Opening of Epoxides with Thiols, Acetic Anhydride, and Alcohols under Solvent-free Conditions
作者:Sweety Singhal、Suman L. Jain、Bir Sain
DOI:10.1246/cl.2008.620
日期:2008.6.5
An efficient and simple protocol for regioselective ring opening of epoxides with thiols, aceticanhydride, and alcohols using 16 wt % MoO3 supported on alumina as a recyclable catalyst is described.
Erbium(III) Triflate is a Highly Efficient Catalyst for the Synthesis of β-Alkoxy Alcohols, 1,2-Diols and β-Hydroxy Sulfides by Ring Opening of Epoxides
ring-opening reaction of epoxides with erbium(III) triflate are described. Epoxides can be cleaved under neutral conditions with alcohols and thiols in the presence of catalytic amounts of Lewis acid, affording the corresponding β-alkoxy alcohols and β-hydroxy sulfides in high yields. In water, epoxide ring opening occurs to produce the corresponding diols in good yields epoxides - Lewis acids - nucleophilic
N-Benzoyl arylsulfonamides having the formula
1
are BCL-Xl inhibitors and are useful for promoting apoptosis. Also disclosed are BCL-Xl inhibiting compositions and methods of promoting apoptosis in a mammal.
N-Benzoyl arylsulfonamides having the formula
1
Are BCL-X1 inhibitors and are useful for promoting apoptosis. Also disclosed are BCL-X1 inhibiting compositions and methods of promoting apoptosis in a mammal.
JandaJel as a polymeric support to improve the catalytic efficiency of immobilized-1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) under solvent-free conditions
JandaJel, with its greater spacing between the linear polymeric chains compared to that of polystyrene matrices, is a very efficient support for improving the catalytic efficiency of TBD under SolFC.