Enantiomerically Pure Rhodium Complexes Bearing 1,5-Diphenyl-1,5-cyclooctadiene as a Chiral Diene Ligand. Their Use as Catalysts for Asymmetric 1,4-Addition of Phenylzinc Chloride
摘要:
A rhodium complex coordinated with 1,5-diphenyl-1,5-cyclooctadiene (Ph-cod), [RhCl((R)-Ph-cod)](2), was obtained enantiomerically pure through optical resolution of diastereomeric isomers [Rh(Ph-cod)((R)-1,1'-binaphthyl-2,2'-diamine)]BF4. The enantiomerically pure rhodium complexes showed high catalytic activity and enantioselectivity (up to 98% ee) in the asymmetric 1,4-addition of phenylzinc chloride to alpha,beta-unsaturated ketones and esters in the presence of chlorotrimethylsilane.
3 + 2 Cycloaddition via a Diels-Alder/retro-Diels-Alder sequence: Tandem cyclopentadienyl annulation of a 1,5-cyclooctadiyne synthetic equivalent
作者:Alfonso Dávila、Merrikh S. Ramezanian、Frank R. Fronczek、Mark L. McLaughlin
DOI:10.1016/0040-4039(96)00384-x
日期:1996.4
A novel method of synthesizing a 1,2-bis(ethano) bridged bis(cyclopentadienyl) compound, 6,13-diisopropylidenetricyclo[9.3.01,11.04,8]tetradeca-1(14),4,7,11-tetraene, 5, via a tandem Diels-Alder/retro-Diels-Alder sequence using a 1,5-cyclooctadiyne synthetic equivalent and 6,6-dimethylfulvene i is reported.
Design of a Ribosyltriazole-Annulated Cyclooctyne for Oligonucleotide Labeling by Strain-Promoted Alkyne-Azide Cycloaddition
作者:Pieter van Delft、Wilbert de Witte、Nico J. Meeuwenoord、Gerbrand J. van der Heden van Noort、Frank Versluis、Rene C. L. Olsthoorn、Herman S. Overkleeft、Gijs A. van der Marel、Dmitri V. Filippov
DOI:10.1002/ejoc.201403086
日期:2014.12
A ribosyltriazole ring-fused cyclooctyne was prepared and converted into the corresponding phosphoramidite, which was applied in the automated synthesis of DNA and RNA oligomers. Ensuing strain-promotedalkyne–azidecycloaddition of the obtained oligonucleotides to fluorescent azides yielded the corresponding fluorescent oligonucleotide conjugates.
制备了核糖基三唑环稠合环辛炔并将其转化为相应的亚磷酰胺,用于 DNA 和 RNA 寡聚体的自动合成。随后将获得的寡核苷酸与荧光叠氮化物进行应变促进的炔-叠氮化物环加成反应,产生相应的荧光寡核苷酸缀合物。
1,5-Dibromocycloocta-1,5-diene
作者:A. Dávila、M. L. McLaughlin、F. R. Fronczek、S. F. Watkins
DOI:10.1107/s0108270196012322
日期:1997.1.15
The molecule of the title compound, C8H10Br2, lies on a crystallographic twofold axis, The eight-membered ring has a twist-boat conformation in which the two olefin planes form a dihedral angle of 74.7 (1)degrees with one another, The C-Br distance is 1.928(3) Angstrom and the C=C distance is 1.314(3) Angstrom.