Development of practical metal-catalyzed carbenoid reactions for environmentally benign chemistry

铜催化氧鎓叶立德形成-[2，3]位移法立体选择性合成抗癌药物月桂酰亚胺的C3-C12二氢吡喃部分（对甲氧基苄氧基）-7-甲基-2-辛酮在四氢呋喃-二氯甲烷（4：1）中回流进行，具有优异的立体选择性（97：1）。3）得到（2 R，6S）-2-烯丙基-6-[（2 R）-3-（对甲氧基苄氧基）-2-甲基丙基]-3-二氢吡喃酮（2），其为主要异构体，产率为82%。吡喃酮是Mulzer合成laulimalide及其衍生物的关键中间体。二铑催化C-H胺化合成免疫调节剂（+）-Conagenin及其类似物实现了免疫调节剂（+）-Conagenin的立体选择性合成。以市售的光学活性3-羟基-2-甲基丙酸甲酯为原料，采用铑催化的C-H胺化反应和螯合控制反应，制备了胺和羧酸部分。 ...更多信息 d削减是关键步骤。此外，还用类似的方法合成了Conagenin的去甲基类似物。（叔丁基二甲基甲硅烷基氧基）-2-甲基丙基氨基甲酸酯：光学活性单保护基2-氨基-2-甲基-1，3-丙二醇的简便制备铑（II）催化的（S）-3-（2-甲基-1，3-丙二醇）C-H胺化反应由（S）-2-甲基-3-羟基丙酸甲酯容易地合成了（叔丁基二甲基甲硅烷氧基）-2-甲基丙基氨基甲酸酯，比它们的2-（甲氧羰基）丙基衍生物更顺利地以优异的产率得到相应的恶唑烷酮。得到的恶唑烷酮被有效地转化为（R）-单保护的和（S）-单保护的2-氨基-2-甲基-1，3-二氧杂环己烷，3-丙二醇类化合物. Pachastrissamine的不对称合成（Jaspin B）以二铑（II）催化的C-H胺化和不对称双羟基化为关键步骤对映选择性全合成脱水植物鞘氨醇pachastrissamine（jaspin B）是通过Sharpless不对称双羟基化和二铑（II）催化的C-H胺化作为关键步骤得到的。少

Stereoselective Synthesis of C3-C12 Dihydropyran Portion of Antitumor Laulimalide Using Copper-catalyzed Oxonium Ylide Formation-[2,3] ShiftCopper-catalyzed oxonium ylide formation-[2,3] shift of (5S,7R)-5-allyloxy-1-diazo-8-(p-methoxybenzyloxy)-7-methyl-2-octanone proceeded in tetrahydrofuran-dichloromethane (4:1) under reflux with an excellent stereoselectivity (97:3) to give (2R,6S)-2-allyl-6-[(2R)-3-(p-methoxybenzyloxy)-2-methylpropyl]-3-dihydropyranone (2) as a major isomer in 82% yield. The resultant pyranone was converted to the key intermediate of the Mulzer's laulimalide synthesis and its derivatives.Synthesis of an Immunomodulator (+)-Conagenin and Its Analogs using Dirhodium(II)-catalyzed C-H AminationStereoselective synthesis of an immunomodulator (+)-conagenin was achieved. Both amine and carboxylic acid moieties were prepared from commercially available optically active methyl 3-hydroxy-2-methylpropanoate using dirhodium(II)-catalyzed C-H amination and chelation-controlle … More d reductions as key steps. In addition, demethyl analogs of conagenin were synthesized using similar procedures.Dirhodium(II)-catalyzed C-H Amination Reaction of (S)-3-(tert-Butyldimethylsilyloxy)-2-methylpropyl Carbamate : A Facile Preparation of Optically Active Monoprotected 2-Amino-2-methyl-1,3-propanediolDirhodium(II)-catalyzed C-H amination reaction of (S)-3-(tert-butyldimethylsilyloxy)-2-methylpropyl carbamate, which was easily prepared from methyl (S)-2-methyl-3-hydroxypropanoate, proceeded more smoothly than those of their 2-(methoxycarbonyl)propyl derivative to give the corresponding oxazolidinone in excellent yield. The resulting oxazolidinone was converted efficiently into both (R)-monoprotected and (S)-monoprotected 2-amino-2-methyl-1,3-propanediols.Enantioselective Synthesis of Pachastrissamine (Jaspin B) using Dirhodium(II)-catalyzed C-H Amination and Asymmetric Dihydroxylation as Key StepsEnantioselective total synthesis of anhydrophytosphingosine pachastrissamine (jaspin B) was achieved using the Sharpless asymmetric dihydroxylation and dirhodium(II)-catalyzed C-H amination as key steps. Less