139079-91-7Relevant academic research and scientific papers
Synthesis of Enantiopure Homoallylic Alcohols and Ethers by Diastereoselective Allylation of Aldehydes
Tietze, Lutz F.,Schiemann, Kai,Wegner, Christoph,Wulff, Christian
, p. 1164 - 1172 (2007/10/03)
Enantiopure homoallylic alcohols 5, which are important building blocks in organic synthesis, are obtained with an ee of greater than 99percent and a yield of 75-95percent by cleavage of the secondary homoallylic ethers 4 using sodium in liquid ammonia.The ethers 4 are formed with excellent diastereoselectivity and in 52-89percent yield by treatment of the aldehydes 1 with the trimethylsilyl ether of N-trifluoroacetylnorpseudoephedrine (2) in the presence of a catalytic amount of TMS triflate or TMS borontriflate, followed by addition of allylsilane 3.Nearly all achiral aliphatic aldehydes employed gave a diastereoselectivity of over 99:1.With the chiral aldehydes 24, the difference between matched and mismatched pairs was low; this reveals that there is strong reagent control.- Keywords: allylations; allylsilanes; double stereodifferentiation; ephedrine; homoallylic alcohols
