41921-28-2Relevant academic research and scientific papers
Regio- and stereoselective nickel-catalyzed homoallylation of aldehydes with 1,3-dienes
Kimura, Masanari,Ezoe, Akihiro,Mori, Masahiko,Iwata, Keisuke,Tamaru, Yoshinao
, p. 8559 - 8568 (2007/10/03)
Ni(acac)2 catalyzes homoallylation of aldehydes with 1,3-dienes in the presence of triethylborane. Triethylborane serves as a reducing agent delivering a formal hydride to the C2 position of 1,3-dienes, thus generating a formal homoallyl anion species and enabling the novel homoallylation of aldehydes. The reaction proceeds smoothly at room temperature in the absence of any phosphane or nitrogen ligands and is highly regioselective and stereoselective for a wide variety combination of aldehydes and 1,3-dienes: e.g., isoprene and benzaldehyde combine to give a mixture of anti- and syn-1-phenyl-3-methyl-4-penten-1-ol (2.2) in a ratio of 15:1 in 90% yield. Under the conditions, sterically congested aliphatic aldehydes and ketones show low yields. In such cases, diethylzinc serves as a substitute for triethylborane and yields the expected products in good yields with similarly high regio- and stereoselectivity. 1,3-Cyclohexadiene is one exception among 24 kinds of dienes examined and undergoes allylation (not homoallylation) selectively.
New preparation of benzylic zinc reagents via a fragmentation reaction
Piazza, Claudia,Millot, Nicolas,Knochel, Paul
, p. 88 - 95 (2007/10/03)
The fragmentation of sterically hindered homobenzylic zinc alcoholates proceeds readily leading to benzylic zinc reagents free from any Wurtz-coupling product. Reaction of these organometallic intermediates with various aldehydes produces new homobenzylic
Asymmetric Allylation with a New Chiral Allylating Agent Prepared from Tin(II) Triflate, Chiral Diamine, and Allylaluminium
Minowa, Nobuto,Mukaiyama, Teruaki
, p. 3697 - 3704 (2007/10/02)
A chiral allylating agent, readily generated from tin(II) trifluoromethanesulfonate (tin(II) triflate), chiral diamines derived from (S)-proline and allylaluminium, is efficiently employed in the asymmetric allylation of aldehydes and epoxide.Reaction of
