β-Alkoxyacrylates in radical cyclizations: Remarkably efficient oxacyle synthesis
摘要:
Beta-alkoxyacrylates were found to be exceptionally efficient radical acceptors in radical-mediated intramolecular cyclizations. For example, reaction of 5-bromo-2-pentanol with ethyl propiolate, tributylstannane-mediated radical cyclization, and hydrolysis yielded (+/-)-(cis-6-methyltetrahydropyran-2-yl)acetic acid, a known component of civet.
Multicatalytic Synthesis of Complex Tetrahydrofurans Involving Bismuth(III) Triflate Catalyzed Intramolecular Hydroalkoxylation of Unactivated Olefins
作者:Brendan D. Kelly、Julia M. Allen、Rachel E. Tundel、Tristan H. Lambert
DOI:10.1021/ol900198r
日期:2009.3.19
A multicatalytic synthesis of complex tetrahydrofurans has been developed involving a Bi(OTf)(3)-Catalyzed nucleophilic addition/hydroalkoxylation sequence. Complex tetrahydrofuranyl products may be formed rapidly in high yield and with good diastereoselectivity. The demonstrated scope of hydroalkoxylation has also been expanded to include substrates bearing useful functional handles including carboxylate ester, olefin, nitrile, and nitro groups.
Thione Esters as Substrates for the Stereoselective Alkylation of Model Compounds of Nonactic Acids
作者:François Loiseau、Inga Kholod、Reinhard Neier
DOI:10.1002/ejoc.200901513
日期:2010.8
relative configurations could be achieved. In the third route the thioneester 18 was deprotonated with tBuOK. At temperatures below -78 °C, the enolate maintained the cis configuration of the substituents at the tetrahydrofuran ring. The alkylated product 12 could be isolated with a satisfactory cis/trans ratio of 85:15. The modelcompound 12 could be successfully transformed into more hydrophobic derivatives
β-Alkoxyacrylates in radical cyclizations: Remarkably efficient oxacyle synthesis
作者:Eun Lee、Sung Tae Jin、Chulbom Lee、Park Cheol Min
DOI:10.1016/s0040-4039(00)74101-3
日期:1993.7
Beta-alkoxyacrylates were found to be exceptionally efficient radical acceptors in radical-mediated intramolecular cyclizations. For example, reaction of 5-bromo-2-pentanol with ethyl propiolate, tributylstannane-mediated radical cyclization, and hydrolysis yielded (+/-)-(cis-6-methyltetrahydropyran-2-yl)acetic acid, a known component of civet.