S-Alkyl 2-(dialkoxyphosphoryl)alkanethioates 3 can readily be prepared by the reaction of 2-(dialkoxyphosphoryl)alkanoyl chlorides 1 with thiols 2 in the presence of triethylamine. Only S-propyl 2-(dialkoxyphosphoryl)propanethioate (3b) gave synthetically useful Horner reactions: it was converted into the α-potassiopropanethioate anion by treatment with potassium carbonate in a small amount of water at room temperature. The Horner reaction between this anion and aldehydes 4 gave various α,β-unsaturated thioesters 5 with an α-substituted methyl group. Application of this method to the cis/trans ethyl 2-formyl-3,3-dimethyl-1-cyclopropylcarboxylate esters 4f led to the 2-(propylthiocarbonyl)-2-propenyl pyrethroid derivatives 5f.
S-烷基 2-(二烷氧基膦酰基)烷
硫基酯 3 可方便地通过 2-(二烷氧基膦酰基)烷酰
氯 1 与
硫醇 2 在
三乙胺存在下反应制备。仅 S-丙基 2-(二烷氧基膦酰基)
丙硫基酯(3b)给出了合成上有用的 Horner 反应:在室温下用
水处理时,它被转化为少量的
碳酸钾处理后得到的 α-
膦酸丙硫基酸根离子。该离子与醛 4 的 Horner 反应生成各种具有 α-取代甲基的 α,β-不饱和
硫酯 5。将此方法应用于顺/反式乙基 2-甲酰基-3,3-二甲基-1-环丙基
羧酸酯 4f 时,得到了具有 2-丙基
硫代碳酰基-2-
丙烯基的菊酯衍
生物 5f。