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1.
蒋耀忠 《分子催化》1997,11(6):401-407
重点报道了以(1R,2S)或(1S,2R)-1,2-二苯基-2-氨基乙醇衍生物手笥配体的合成及其用于不对称催化反应的研究,如去氢氨基酸的氢化,醛的乙基锌加成,酮的还原,活泼亚甲基化合物的烷基化,醛的硅腈化和瑞福马斯基反应等。研究了手性配体的结构,底物和反件等对上述反应的对映造反性和催化活性的影响。  相似文献   

2.
萘普生[(S)2(6甲氧基2萘基)丙酸]是一种非常重要的非麻醉性消炎镇痛药.周宏英等[1]报道了用手性膦配体DDPPI对2(6甲氧基2萘基)乙醇进行不对称羰基化反应合成了萘普生甲酯.本文用(2R,3R)酒石酸二甲酯为手性辅助剂,以...  相似文献   

3.
以R-(+)-Pulegone为起始原始经1,4-加成、溴代、水解、氧化等9步反应合成了手性辅助试剂(+)-1S,2R,5S-8-β-萘基薄荷醇及其关向异构体(-)-1R,2R,5S-8-β萘基新薄荷醇,总收率分别为24.0%和22.6%。  相似文献   

4.
R(-)四氢噻唑-2-硫酮-4-羧酸[简称R(-)TTCA]可作为检查尿样中CS2含量的标准试剂,我们对其结构[1]及性质进行了研究,发现它有很好的手性识别功能,可作为新的拆分试剂对R,S-α-苯乙胺进行拆分.光学活性的α-苯乙胺已被广泛地用来代替光...  相似文献   

5.
(R)-乙基-2-吡啶亚砜与(4R,5R)-二(羟基-二苯基-甲基)-2,2-二甲基-1,3-二氧戊环(TAD-DOL)可以形成物质的量比为1∶1的手性包结晶体,X射线衍射分析确定该晶体属单钭晶系,P21空间群,a=0.9701(2)nm,b=0.9953(2)nm,c=1.7392(2)nm;β=92.079°(14),V=1.6781(5)nm3,Z=2,Dc=1.230g/cm3,分子式C38H39NO5S,Mr=621.76,最终偏离因子R=0.0351,RW2=0.0772,Flack值为0.1(2).结构分析表明,主客体存在分子间氢键.光学纯的TADDOL与消旋的乙基吡啶亚砜(1)作用时,TADDOL对1具有很好的手性识别能力,选择性地与1的一个对映体形成氢键,长成晶体.参照晶体结构确定了1的两个对映体的绝对构型  相似文献   

6.
报道了以手性3-N,N,-二甲氨基-1,2-二苯基醇为配体,催化苯甲醛与乙基锌对映选择了加成反应中的非线性效应:1R,2S构型的配体使反应呈非线性效应;而1S,2R构型的配体使反应呈负非线性效应。  相似文献   

7.
在THF溶液中,40-60℃及0.3-0.5MPa氢压条件下,[RuCl2(cht)]2+(S)-BINAP手性催化剂体系催化不饱和手性缩酮2选择加氢,再经脱去手性二醇,即可高立体选择性地制得(R)-3-甲基环十五烷酮(4,(R)-(-)-麝香酮),化学收率≥95%,光学纯度≥97%.手性缩酮2由D-苏糖醇或D-葡萄糖衍生的手性二醇3与3-甲基环十五烯-2-酮1生成.  相似文献   

8.
以( - )1 R,2 S2氨 基1 ,2二苯 基乙 醇 作为 手性 源, 与取 代 水杨 醛 缩合 制 备 了系 列 手性 Schiff 碱配 体,考察 了该类配体的二价铜配合物及配体与 Cu( C H3 C N)4 Cl O4 组成的原位 体系对2 ,5二甲基2 ,4己二烯与 重氮乙酸 L薄 荷酯的环丙烷化反应的催化作用. 结果表明, Cu(Ⅱ) 配合物尽管具有较高的催化活性,但几乎没有光 学选择性,而原 位体系 则表 现出极 高的 催化活 性和 一定的 光学选择性,化学收率为903 % , 顺 式体e .e .值达到30 %  相似文献   

9.
黄锦霞  李焰 《应用化学》1998,15(2):79-81
(2S,3R)┐谷象虫聚集信息素的合成黄锦霞*李焰马兴泉陈祖兴徐章煌(湖北大学化学系武汉430062)关键词(2S,3R)-谷象虫聚集信息素,合成,不对称顺式醇醛缩合反应,N-莰烷-磺内酰胺1997-07-14收稿,1997-09-29修回湖北省自然...  相似文献   

10.
在催化量的手性催化剂存在下,利用1-苯磺酰基-3-丁烯-2-酮与异戊二烯的不对称催化Diels-Alder反应,合成了(R)-α-萜品醇5,光学纯度值达到92%.  相似文献   

11.
A facile and practical synthesis of enantiomerically pure (L) or (D)-threo-Ifenprodil was accomplished from (1S, 2S)- and (1R, 2R)-threo-1-(p-nitrophenyl)-2-amino-propan-1, 3-diol via 3-phenylthio derivatives followed by Raney nickel reduction and conversion of the aromatic amine into phenol.  相似文献   

12.
The stereoisomers of cis-2-halocycloalkanols were resolved by a kinetically controlled transesterification with vinyl acetate in the presence of lipases in organic media. High enantioselectivities (ee >98%) and good isolated yields were obtained for all substrates using the appropriate lipase. Burkholderia cepacia lipase was the most efficient enzyme for the resolution of these substrates. The enantiomeric purities of the compounds were defined by derivatization with Mosher’s acid and the absolute configurations were determined by chemical correlation.  相似文献   

13.
Thanks to the successive use of two esterases with different regioselectivities and conventional organic chemistry we have synthesized (1R,2S) and (1S,2S) dehydrocoronamic acids.  相似文献   

14.
15.
《Tetrahedron: Asymmetry》2007,18(18):2218-2226
The trans-configured fosfomycin analogue, diethyl (1S,2S)-1,2-epoxy-3-hydroxypropylphosphonate, was synthesised by the intramolecular Williamson reaction of diethyl (1S,2R)-1,3-dihydroxy-2-mesyloxypropylphosphonate. The cis-analogue was obtained as O-ethyl or O,O-diethyl (1R,2S)-1,2-epoxy-3-hydroxypropylphosphonates, when (1R,2R)-1,3-dihydroxy-2-mesyloxypropylphosphonate or its 3-O-trityl derivative were used as starting materials, respectively. The intramolecular Williamson cyclisations of diethyl (1S,2R)- and (1R,2S)-1-benzyloxy-3-hydroxy-2-mesyloxypropylphosphonates led to diethyl (1S,2S)- and (1R,2S)-2,3-epoxy-1-benzyloxypropylphosphonates, respectively, with the concomitant formation of diethyl (E)-1-benzyloxy-3-hydroxyprop-1-en-1-phosphonate. From diethyl (1S,2S)- and (1R,2S)-2,3-epoxy-1-benzyloxypropylphosphonates, enantiomerically pure diethyl (1S,2S)- and (1R,2S)-1,2-dihydroxypropylphosphonates were obtained by catalytic hydrogenation, while diethyl (1S,2S)- and (1R,2S)-3-acetamido-1,2-dihydroxypropylphosphonates were produced after epoxide ring opening with dibenzylamine, acetylation and hydrogenolysis.  相似文献   

16.
Racemic di-p-methoxyphenyl amino alcohol was synthesized in three steps. Optically pure di-p-methoxyphenyl amino alcohols were obtained by recrystallization. The absolute configuration of the amino alcohol was determined by X-ray crystallography.  相似文献   

17.
《Tetrahedron: Asymmetry》1999,10(2):207-211
The reaction of 2-lithiophenyldiphenylphosphine with phosphorus trichloride afforded the new unsymmetric phosphine, dichloro(2-diphenylphosphinophenyl)phosphine (4). Condensation of 4 with (a) (2R,3R)-dimethyl tartrate or (b) (S)-binaphthol in the presence of triethylamine gave new chiral phosphine-phosphonite ligands, (2R,3R)-[2-(2′-(diphenylphosphino)phenyl)-4,5-bis(carbomethoxy)-1,3,2-dioxaphospholane] ((2R,3R)-5) and (S)-[2-(diphenylphosphino)benzene][1,1′-binaphthalen-2,2′-diyl]phosphonite] ((S)-6). The analogous reaction of 4 with (1R,2S)-ephedrine using N-methylmorpholine as the base, gave [2-(2′-(diphenylphosphino)phenyl)-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidine] (7) as a 95:5 mixture of diastereoisomers.  相似文献   

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