Development and Application of New Transformations of Organosulfur Compounds Utilizing Magnesium Amides

在回流乙醚中，2，2，6，6-四甲基哌啶与溴化乙基镁原位生成的四甲基哌啶镁试剂(RSOCH_2R^1)与亚砜(RSOCH_2R^1)在室温下反应生成相应的二硫代缩醛(RSCHR^1SR)。在α-和β-位都含有氢的亚砜(RSOCHR^1CHR^2R^3)与镁酰胺反应得到相应的乙烯基硫化物(RSCR^1=CR^2R^3)，并伴随相应的二硫缩醛。阐明了生成含硫稳定碳离子中间体的途径，并将这些反应扩展到一系列有机硫化合物的合成。含α-氢的亚砜(S)与二异丙胺镁试剂的反应，二异丙胺与过量…原位生成的二异丙胺镁试剂适量的格氏试剂(R^3MgBr)使相应的硫化物(RSCR^1R^2R^3)生成。光学活性硫化物可以得到高达75%的e.e。二异丙胺和乙基溴化镁生成的二异丙氨基镁试剂先与α位含氢的亚硫醚(R^1SOCHR^2R^3)反应生成不对称的二硫代缩醛(R^1SCR^2R^3SR^4)，再与硫醇(R^4SH)反应得到不对称的二硫代缩醛(R^1SCR^2R^3SR^4)。由仲胺(R^3_2NH)和乙基溴化镁生成的(二烷氨基)镁试剂处理乙烯基亚砜(PhSOCHR^1=chR^2)，得到不对称的β-(N，N-二烷氨基)二硫代醛[(PHS)_2CHR^2CHR^2NR^3_2]。在合适的硫醇(R^4SH)存在下，反应生成相应的不对称的β-(N，N-二烷基氨基)二硫代缩醛[(PHS)(R^4S)Chr^1CHR^2Nr^3_2]。(二异丙氨基)镁试剂先与各种酮和醛衍生的烯胺反应，然后再与含α-氢的亚砜反应，得到相应的α-(α-烷硫基)烷基化酮和醛。较少

It was found that sulfoxides bearing hydrogens at the alpha-position only (RSOCH_2R^1) reacted with the tetramethylpiperidinomagnesium reagent, which was generated in situ by treatment of 2,2,6,6-tetramethylpiperidine with ethylmagnesium bromide in refluxing diethyl ether, at room temperature to produce the corresponding dithioacetals (RSCHR^1SR). The treatment of sulfoxides bearing hydrogens both at the alpha- and beta-positions (RSOCHR^1CHR^2R^3) with the magnesium amide was found to afford the corresponding vinyl sulfides (RSCR^1=CR^2R^3) accompanying the corresponding dithioacetals. The pathways leading to the products involving the formation of the sulfur stabilized carbonium ion intermediates were elucidated, and these reactions were extended to syntheses of a range of organosulfur compounds.The reaction of sulfoxides bearing alpha-hydrogen (s) (RSOCHR^1R^2) with the diisopropylaminomagnesium reagent, which was generated in situ by the treatment of diisopropylamine with an excess … More amount of appropriate Grignard reagents (R^3MgBr), resulted in the formation of the corresponding sulfides (RSCR^1R^2R^3). Optically active sulfides could be obtained up to 75% e.e. by using optically active sulfoxides or secondary amines.The (diisopropylamino) magnesium reagent, generated from diisopropylamine and ethylmagnesium bromide, was treated with thiols (R^4SH) prior to the interaction with sulfoxides bearing hydrogen (s) at the alpha-position (R^1SOCHR^2R^3) to afford unsymmetrical dithioacetals (R^1SCR^2R^3SR^4).The treatment of vinyl sulfoxides (PhSOCHR^1=CHR^2) with (dialkylamino) magnesium reagents, generated from secondary amines (R^3_2NH) and ethylmagnesium bromide, proved to give unsymmetrical beta- (N,N-dialkylamino) dithioacetals [(PhS) _2CHR^1CHR^2NR^3_2]. The reaction in the presence of an appropriate thiol (R^4SH) lead to the formation of the corresponding unsymmetrical beta- (N,N-dialkylamino) dithioacetals [(PhS) (R^4S) CHR^1CHR^2NR^3_2].Tretment of the (diisopropylamino) magnesium reagent with enemines, derived from various ketones and aldehydes, prior to the interaction with sulfoxides bearing alpha-hydrogens gave the corresponding alpha- (alpha-alkylthio) alkylated ketones and aldehydes. Less