Completely stereoselective synthesis of all four stereoisomeric 1-carbamoyloxy-1,3-alkadienes via anti-diastereoselective homoaldol reaction from aldehydes and a single carbon-three-unit
作者:Ede van Hülsen、Dieter Hoppe
DOI:10.1016/s0040-4039(00)61897-x
日期:1985.1
titanium-mediated addition to aldehydes, 4 gives (1)-(3*4*)-enol carbamates 7. A stereospecific Peterson elimination (borontriflouride- or base-mediated) introduces the second double bond either with (3)- or with (3)-configuration. So just by reagent selection for each of the two steps, (1,3)-, (1,3)-, (1,3)-, or (1,3)- dienes 8 - 11, respectively, are prepared with stereoselectivities up to > 99.7%
两者(锂化) -和()-3-三甲基甲硅烷基-2-丙烯基,二异丙基氨基甲酸叔丁酯2次,得到(2 ) -锂化合物3。铝或钛介导的醛加成反应4得到(1 )-(3 * 4 *)-烯醇氨基甲酸酯7。立体定向的彼得森消除(硼酸通酯或碱基介导的)引入具有(3 )-或具有(3 )-构型的第二个双键。因此,只要通过选择试剂用于每个两步的,(1 ,3 ) - ,(1 ,3 ) - ,(1 ,3 ) - ,或(1 ,3 ) -二烯类8 - 11分别制备的立体选择性高达> 99.7%