A new synthesis of functionalized 6,8-dioxabicyclo[3.2.1]octanes
作者:Norbert Daude、Ulrike Eggert、H. M. R. Hoffmann
DOI:10.1039/c39880000206
日期:——
Functionalized 6,8-dioxabicyclo[3.2.1]octanes are prepared efficiently in two steps from aldehydes and methyl vinyl ketone.
由醛和甲基乙烯基酮分两步有效制备官能化的6,8-二氧杂双环[3.2.1]辛烷。
Facile synthesis of biarylmethanes and tetrasubstituted arenes <i>via</i> a base-mediated [3 + 3] benzannulation reaction of Morita–Baylis–Hillman adducts and unsaturated sulfones
作者:Deepak Yadav、Sunil K. Sharma、Rajeev S. Menon
DOI:10.1039/c9ob00214f
日期:——
A facile DBU-mediated [3 + 3] benzannulation reaction of 1,3-bis-sulfonyl propenes and Morita–Baylis–Hillman (MBH) bromides is described. The benzannulation reaction afforded bis-sulfonyl biarylmethanes/arenes with complete regioselectivity. The products may be converted readily into corresponding benzophenones via site-selective benzylic oxidation.
Rhodium(I)- or ruthenium(II)-catalyzed direct coupling of vinyl ketones with aldehydes and the subsequent reduction to give aldol derivatives anti-selectively
作者:Susumu Sato、Isamu Matsuda、Masahiro Shibata
DOI:10.1016/0022-328x(89)80096-8
日期:1989.11
A vinyl ketone reacts with an aldehyde to give an α-methylene-β-hydroxyalkanone with the concomitant formation of the vinyl ketone dimer in the presence of catalytic amount of RhH(PPh3)4 or RuH2(PPh3)4 under almost neutral conditions. The selectivity of the cross-coupling product is remarkably improved in the presence of an extra mole of aldehyde. This type of cross-coupling is explained by the intermediacy