Development of Synthetic Radical Reactions of Cyclic Compounds based on Characteristics of Silicon.

基于硅特性的环状化合物自由基合成反应的进展。

• 批准号: 06453135
• 负责人: OSHIMA Koichiro
• 金额: $ 4.67万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06453135/
• 关键词: Silacyclobutane; Silacyclopentane; Radical Cyclization; Triethylborane; Tributyltin Hydride; Mixed Acetal; Aldol Reaction; α-ヨードアシルシラン; 2-ハロシラシクロペンタン; 7-エンド環化

1.1-Allyloxy-2-bromo-1-phenylsilacyclopentane was synthesized by a ring-enlargement reaction of 1-allyloxy-1-phenylsilacyclobutane with LiCHBr_2. The treatment of 1-allyloxy-2-bromo-1-phenylsilacyclopentane with n-Bu_3SnH in the presence of a catalytic amount of Et_3B provided 2-oxa-1-silabicyclo [3.3.0] octane, which was converted into 1,3,6-triol by an oxidative cleavage of silicon-carbon bonds with H_2O_2. An intermolecular radical addition of 2-iodosilacyclopentane to acetylenic compounds afforded the corresponding iodoalkenes.2.Treatment of ethyl benzoate or isopropyl formate with tert-butyldimethylsilyldibromomethyllithium gave alkyl silyl mixed acetal via 1,3-rearrangement of silyl group from carbon to oxygen. The reaction of the mixed acetals with allylsilane in the presence of Lewis acid afforded allylated ethers.3.Treatment of 2-halo-2-trimethysilyloxirane with metal salts such as ZnCl_2, ZnBr_2, NaI,and AgBF_4 gave the corresponding alpha-haloacylsilanes in good yields. An addition of triethylborane to haloacylsilane provided boron enolate which reacted with aldehydes to give aldol type adducts with high stereoselectivity.

以1-烯丙氧基-1-苯基硅环丁烷为原料，与LiCHBr_2进行扩环反应，合成了1.1-烯丙氧基-2-溴-1-苯基硅环戊烷。1-烯丙氧基-2-溴-1-苯基硅杂环戊烷在催化量的Et_3B存在下与n-Bu_3SnH反应生成2-氧杂-1-硅双环[3.3.0]辛烷，后者经H_2O_2氧化裂解硅碳键生成1，3，6-三醇。2.苯甲酸乙酯或甲酸异丙酯与叔丁基二甲基硅基二溴甲基锂反应，通过硅基碳原子到氧原子的1，3-重排反应得到烷基硅基混合缩醛。3.用ZnCl_2、ZnBr_2、NaI和AgBF_4等金属盐处理2-卤代-2-三甲基硅基环氧乙烷，以较好的产率得到相应的α-卤代酰基硅烷。三乙基硼烷与卤代酰基硅烷加成得到硼烯醇化物，硼烯醇化物与醛反应得到高立体选择性的羟醛型加成物。

项目成果

Koichiro Oshima: "Preparation of Alkyl Silyl Acetals from Carboxylic Esters with tert-Butyldimethylsilyldihalomethyllithium. 1,3-Rearrangement of Silyl Group from Carbon to Oxygen" Chemistry Lett.461-462 (1995)

Koichiro Oshima：“用叔丁基二甲基甲硅烷基二卤甲基锂从羧酸酯制备烷基甲硅烷基缩醛。甲硅烷基从碳到氧的 1,3-重排” Chemistry Lett.461-462 (1995)

Koichiro Oshima: "Triethylborane-Induced Radical Cyclization of 1-Allyloxy-2-halosilacyclopentane. Stereoselective Synthesis of 1,3,6-Triols Starting from Silacyclobutane" Bull.Chem.Soc.Jpn.68. 625-634 (1995)

Koichiro Oshima：“三乙基硼烷诱导的 1-烯丙氧基-2-卤代硅杂环戊烷的自由基环化。从硅杂环丁烷开始立体选择性合成 1,3,6-三醇”Bull.Chem.Soc.Jpn.68。

Koichiro Oshima: "Preparation of alkyl silyl acetals from carboxylic esters with t-butyldimethylsilyl-dihalomethyllithium" Chemistry Lett.,. 461-462 (1995)

Koichiro Oshima：“用叔丁基二甲基甲硅烷基-二卤甲基锂从羧酸酯制备烷基甲硅烷基缩醛”，《化学快报》。

Koichiro Oshima: "Preparation of alkyl silyl acetals from carboxylic esters with t-butyldimethylsilydihalomethyllithium" Chemistry Lett.,. 461-462 (1995)

Koichiro Oshima：“用叔丁基二甲基甲硅烷基二卤甲基锂从羧酸酯制备烷基甲硅烷基缩醛”，Chemistry Lett.，。

Koichiro Oshima: "Triethylborane-induced radical cyclization of 1-allyloxy-2-halosilacyclopentane" Bull. Chem. Soc. Jpn.,. 68. 625-634 (1995)

Koichiro Oshima：“三乙基硼烷诱导的 1-烯丙氧基-2-卤硅杂环戊烷的自由基环化”公牛。