共查询到20条相似文献,搜索用时 78 毫秒
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烯丙基溴与金属钐在室温条件下、THF溶剂中反应生成中间体烯丙基溴化钐,烯丙基溴化钐再与α,β-不饱和醛、酮反应生成高烯丙基醇.烯丙基溴化钐与α,β-不饱和醛、酮发生1,2-加成反应,其与α,β-不饱和酮的反应几乎定量进行,表明该反应具有很好的区域选择性.产物的结构通过IR,1H NMR和MS光谱确证. 相似文献
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研究了不同脂肪族和芳香族醛与6-甲基-6-苯基-7-烯-1,5-辛二醇的烯丙基转移反应, 同时考察了溶剂对反应的影响. 结果发现, 在In(OTf)3催化下, 以甲苯为溶剂, 由脂肪族醛合成的直链高烯丙基醇较芳香族醛具有较高的产率和较好的选择性, 所得产物结构经1H NMR, 13C NMR, IR, HRMS表征. 相似文献
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以6,7-十二烷二酮(或1,2-环烷基二酮)和3-碘-2-碘甲基-1-丙烯为原料,铟粉为催化剂,在水相中经烯丙基化反应合成了4个新型的单烯丙基化产物[7-羟基-7-(2-碘甲基-烯丙基)-十二烷-6-酮和2-羟基-2-(2-碘甲基-烯丙基)-环烷酮]和3个新型的双烯丙基化产物{4-亚甲基-1,2-二戊基-1,2-环戊二醇,2-羟基-2-[2-(1-羟基-2-羰基-环癸基甲基)-烯丙基]-环癸酮和2-羟基-2-[2-(1-羟基-2-羰基-环十二基甲基)-烯丙基]-环十二烷酮},其结构经1H NMR,IR和HR-MS表征。 相似文献
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以邻烯丙基双酚A、多聚甲醛和烯丙基胺为原料,采用无溶剂的方法合成了一种不含β-氢的苯并噁嗪(2,2-二(3,8-二烯丙基-3,4-二氢-2H-1,3-苯并噁嗪)-丙烷(B—dbo).GPC和元素分析结果表明,此噁嗪中间体主要是单量体和二聚体.用FTIR和^1H NMR对中间体结构进行了表征.结果表明,此苯并噁嗪的分子结构中存在三种反应官能团:噁嗪环、N-烯丙基、Ar-烯丙基.用DSC和FTIR研究三种反应基团在固化时的反应情况.将双酚A、邻烯丙基双酚A、TiCl4和PCl5作为催化剂按适量的比例加入B—dbo中,用DSC研究其固化行为,并对TiCl4催化试样在不同的固化温度下进行FTIR测试分析,提出在TiCl4催化下苯并噁嗪环副反应及开环固化机理. 相似文献
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Denis N. Bobrov 《Tetrahedron letters》2008,49(26):4089-4091
We report herein olefin exchange-mediated cyclopropanation of nitriles with homoallylic alcohols. The use of homoallylic alcohols is central to the successful implementation. 相似文献
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Under the conditions of ruthenium-catalyzed transfer hydrogenation employing 2-propanol as the terminal reductant, 1,1-disubstituted allenes 1a- h engage in reductive coupling to paraformaldehyde to furnish homoallylic alcohols 2a- h. Under identical transfer hydrogenation conditions, 1,1-disubstituted allenes engage in reductive coupling to aldehydes 3a- f to furnish homoallylic alcohols 4a- n. In all cases, reductive coupling occurs with branched regioselectivity to deliver homoallylic alcohols bearing all-carbon quaternary centers. 相似文献
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A simple procedure has been developed for conducting tin-mediated deoximation and allylation reactions of aldoximes in water to form homoallylic alcohols. Employing the new conditions, various homoallylic alcohols were produced in good to excellent yields. 相似文献
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A general approach to the diastereoselective synthesis of Delta(2)-isoxazolines via magnesium-mediated, hydroxyl-directed diastereoselective nitrile oxide cycloadditions of homoallylic alcohols and monoprotected homoallylic diols is disclosed. A broad spectrum of aliphatic and aromatic nitrile oxides and a variety of homoallylic alcohols participate in the cycloaddition, thus expanding the scope of polyketide building blocks that can be accessed using this strategy. 相似文献
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A new protocol for the palladium chloride-catalyzed direct hydrosulfonamidation of homoallylic alcohols with migration of the double bond is described. This method requires no preactivation of alcohols and the reaction is environmentally benign with water as the only by-product. Various homoallylic alcohols on hydrosulfonamidation with sulfonamides gave the corresponding products in good yields. 相似文献
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Prashant B. Thorat Santosh V. Goswami Sudhakar R. Bhusare 《Tetrahedron: Asymmetry》2013,24(20):1324-1330
An efficient asymmetric synthesis of homoallylic alcohols is described by the allylation of carbonyl compounds using organocatalysts as chiral directors in the presence of tin metal. The effect of chiral environment is also studied on the allylation reactions. This method allows us to obtain two different enantiomers of homoallylic alcohol in the presence of the corresponding chiral compound. The protocol is applied to various aldehydes to obtain high yields and excellent enantioselectivities for the corresponding homoallylic alcohols. 相似文献
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Hao Li 《Tetrahedron letters》2007,48(12):2209-2211
2,2′-Disubstituted ferrocenecarboxaldehydes are subjected to zinc-mediated allylation to form homoallylic ferrocenyl alcohols. The effects of ortho-substituted functional groups on facial selectivities of planar chiral aldehydes were studied and it was found that the corresponding homoallylic alcohols were obtained as single diastereomers in excellent yields. 相似文献
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Luqing Lin Kumiko Yamamoto Dr. Shigeki Matsunaga Prof. Dr. Motomu Kanai 《化学:亚洲杂志》2013,8(12):2974-2983
The chemoselective generation of aldehyde‐derived enolates to realize an aldehyde? aldehyde cross‐aldol reaction is described. A combined Rh/dippf system efficiently promoted the isomerization/aldol sequence by using primary allylic, homoallylic, and bishomoallylic alcohols; secondary allylic and homoallylic alcohols; and trialkoxyboranes that were derived from primary allylic and homoallylic alcohols. The reaction proceeded at ambient temperature under base‐free conditions, thus giving cross‐aldol products with high chemoselectivity. Mechanistic studies, as well as its application to double‐aldol processes under protecting‐group‐free conditions, are also described. 相似文献
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《合成通讯》2013,43(19):3473-3480
Abstract The use of the Barbier‐Grignard reaction, where premixed allyl bromide and the carbonyl compound are added to magnesium in ether, is reported for the synthesis of homoallylic alcohols. This reaction provides good to excellent yields of most homoallylic alcohols with minimal formation of Wurtz coupling products. 相似文献
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A one-pot, convenient method for the preparation of optically active homoallylic alcohols from allyl halides was developed. Allyltrichlorosilanes were generated in situ from allyl halides and trichlorosilane in the presence of cuprous chloride and tertiary amine. Without isolation of the allyltrichlorosilanes, benzaldehyde and chiral biquinoline N,N'-dioxide were introduced into the same flask, producing the corresponding homoallylic alcohols with good to high enantioselectivities. 相似文献