Copper(II)-Catalyzed β-Borylation of Acetylenic Esters in Water
作者:Webster Santos、Cheryl Peck、Joseph Calderone
DOI:10.1055/s-0034-1380524
日期:——
presence of bis(pinacolato)diboron and catalytic amounts of both copper(II) and 4-picoline, substituted alkynoates undergo borylation in a regio-, stereo-, and chemoselective fashion. The reaction is performed under mild conditions using water as solvent and open to the atmosphere to exclusively afford (Z)-β-boryl-α,β-unsaturated esters. A method for the β-borylation of alkynoates has been developed
New Stereoselective Syntheses of Stereodefined 2-Substituted Alkyl 2-Alkenoates and Their Applications
作者:Renzo Rossi、Adriano Carpita、Paolo Cossi
DOI:10.1016/s0040-4020(01)89453-9
日期:——
(Z)-4-(tert-butyldimethylsilyloxy)-2-phenyl-2-butenoate, (Z)-9d, has been employed in a very simple and efficient synthesis of 3-phenyl-5(H)-2-furanone, 12, a metabolite of an hypnotic drug. On the other hand, the procedure employed to prepare esters (E)-10, which involves a configurational inversion, has been used to prepare the (S)-enantiomer of (E)-2,4-dimethyl-2-hexenoic acid, (E)-13, a caste-specific
Total Synthesis of the <i>Schisandraceae</i>
Nortriterpenoid Rubriflordilactone A
作者:Guilhem Chaubet、Shermin S. Goh、Mujahid Mohammad、Birgit Gockel、Marie-Caroline A. Cordonnier、Hannah Baars、Andrew W. Phillips、Edward A. Anderson
DOI:10.1002/chem.201703229
日期:2017.10.9
Full details of the totalsynthesis of the Schisandraceae nortriterpenoid natural product rubriflordilactone A are reported. Palladium- and cobalt-catalyzed polycyclizations were employed as key strategies to construct the central pentasubstituted arene from bromoendiyne and triyne precursors. This required the independent assembly of two AB ring aldehydes for combination with a common diyne component
报道了五味子科降三萜类天然产物 rubriflordilactone A 的全合成细节。钯和钴催化的多环化被用作从溴戊二炔和三炔前体构建中心五取代芳烃的关键策略。这需要独立组装两个AB环醛以与共同的二炔组分结合。人们探索了许多模型系统来研究这两种方法,并建立了具有挑战性的苯并吡喃和丁烯内酯环的安装路线。
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作者:Philip S. Jones、Steven V. Ley、Nigel S. Simpkins、Alan J. Whittle
DOI:10.1016/s0040-4020(01)88114-x
日期:1986.1
The first total synthesis of the diterpene clerodane insect antifeedant ajugarin I (1) has been achieved. The key step of the synthesis discloses the use of the 1,3-dithiolane unit to stereochemically direct the conjugate addition of a but-3-enyl cuprate to set in place the C-10 sp3 carbon centre. The trans-fused ring geometry was obtained by conjugate additon of a vinyl cuprate to an enone and regio
作者:Shermin S. Goh、Guilhem Chaubet、Birgit Gockel、Marie-Caroline A. Cordonnier、Hannah Baars、Andrew W. Phillips、Edward A. Anderson
DOI:10.1002/anie.201506366
日期:2015.10.19
Two enantioselective total syntheses of the nortriterpenoid natural product rubriflordilactone A are described, which use palladium‐ or cobalt‐catalyzed cyclizations to form the CDE rings, and converge on a late‐stage synthetic intermediate. These key processes are set up through the convergent coupling of a common diyne component with appropriate AB‐ring aldehydes, a strategy that sets the stage for
描述了去甲三萜类天然产物 rubriflordilactone A 的两种对映选择性全合成,它们使用钯或钴催化的环化形成 CDE 环,并收敛于后期合成中间体。这些关键过程是通过常见的二炔组分与适当的AB环醛的聚合偶联而建立的,这一策略为该天然产物家族其他成员的合成探索奠定了基础。