Aliphatic α-oxo ketene cyclic dithioacetals 1 were reacted with allyl magne- sium bromide to afford the 1,2-addition products 2.Catalyzed by boron trifluoride etherate,the adducts 2 were etherified by methanol to aff...Aliphatic α-oxo ketene cyclic dithioacetals 1 were reacted with allyl magne- sium bromide to afford the 1,2-addition products 2.Catalyzed by boron trifluoride etherate,the adducts 2 were etherified by methanol to afford the corresponding methyl ethers 3.This process provides a new method for the protection of the acid sensitive hydroxyl group in 2 under mild condition.展开更多
The article presents a new composition for fatliquoring the leather obtained from local secondary products and a stepwise method of fatliquoring process. It was determined that with stepwise fattening, the fatliquorin...The article presents a new composition for fatliquoring the leather obtained from local secondary products and a stepwise method of fatliquoring process. It was determined that with stepwise fattening, the fatliquoring composition can be added stepwise: in the processes of pickling, tanning, dyeing, retanning and fatliquoring. It was revealed that the introduction of etherification in the composition and stepwise method of fatliquoring of the leather, will allow a uniform distribution of the fatliquoring agents in the skin structure, providing an improvement in the performance properties of the finished product.展开更多
文摘Aliphatic α-oxo ketene cyclic dithioacetals 1 were reacted with allyl magne- sium bromide to afford the 1,2-addition products 2.Catalyzed by boron trifluoride etherate,the adducts 2 were etherified by methanol to afford the corresponding methyl ethers 3.This process provides a new method for the protection of the acid sensitive hydroxyl group in 2 under mild condition.
文摘The article presents a new composition for fatliquoring the leather obtained from local secondary products and a stepwise method of fatliquoring process. It was determined that with stepwise fattening, the fatliquoring composition can be added stepwise: in the processes of pickling, tanning, dyeing, retanning and fatliquoring. It was revealed that the introduction of etherification in the composition and stepwise method of fatliquoring of the leather, will allow a uniform distribution of the fatliquoring agents in the skin structure, providing an improvement in the performance properties of the finished product.