Tetrabutylammonium difluorotripheylstannate as a new anhydrous synthetic equivalent to TBAF
作者:Marx Gingras
DOI:10.1016/0040-4039(91)80112-j
日期:1991.12
Tetrabutylammonium difluorotriphenylstannate (1) is the first hypervalent complex of tin acting as a fluorinating agent. In contrast to TBAF and TASF, this crystalline complex is relatively stable up to 210°C and is not hygroscopic or hydrated. Enolsilylether alkylations with alkyl bromides proceeded in good to quantitative yields in the presence of (1), which was kept for years unprotected from moisture
Dephosphonylation of α-fully substituted β-keto phosphonates with LiAlH4; regioselective alkylation of ketones employing phosphonate as a temporary activating group
作者:Shi Yong Lee、Jong Eoun Hong、Won Bum Jang、Dong Young Oh
DOI:10.1016/s0040-4039(97)00975-1
日期:1997.6
Alkylation of β-keto phosphonates is performed by teatment of β-keto phosphonates with n-BuLi, followed by addition of alkyl halides. The acquired α-fully substituted β-keto phosphonates are dephosphonylated by treatment of the lithium enolates with LiAlH4, followed by quenching with aqueous H2SO4 solution. This whole procedure represents a new route to regioselective alkylation of ketones.
β-酮膦酸酯的烷基化是通过用n -BuLi乳化β-酮膦酸酯,然后添加烷基卤来进行的。通过用LiAlH 4处理烯醇锂,然后用H 2 SO 4水溶液淬灭,将获得的α-完全取代的β-酮膦酸酯脱膦酰化。整个过程代表了酮区域选择性烷基化的新途径。
Dreux; Colonge, Bulletin de la Societe Chimique de France, 1955, p. 1312,1315