1300749-80-7Relevant academic research and scientific papers
Enantioselective IrI-catalyzed carbocyclization of 1,6-enynes by the chiral counterion strategy
Barbazanges, Marion,Auge, Mylene,Moussa, Jamal,Amouri, Hani,Aubert, Corinne,Desmarets, Christophe,Fensterbank, Louis,Gandon, Vincent,Malacria, Max,Ollivier, Cyril
, p. 13789 - 13794 (2012/01/06)
Enantioenriched bicyclo[4.1.0]hept-2-enes were synthesized by Ir I-catalyzed carbocyclization of 1,6-enynes. No chiral ligands were used, CO and PPh3 were the only ligands bound to iridium. Instead, the stereochemical information was
Chiral diene-phosphine tridentate ligands for rhodium-catalyzed asymmetric cycloisomerization of 1,6-enynes
Nishimura, Takahiro,Maeda, Yuko,Hayashi, Tamio
supporting information; experimental part, p. 3674 - 3677 (2011/09/14)
Asymmetric cycloisomerization of nitrogen-bridged 1,6-enynes proceeded in the presence of a cationic rhodium complex coordinated with a chiral diene/phosphine tridentate ligand to give high yields of chiral 3-azabicyclo[4.1.0]heptenes with high enantiosel
Tungsten(0)- and rhenium(I)-catalyzed tandem cyclization of acetylenic dienol silyl ethers based on geminal carbo-functionalization of alkynes
Kusama, Hiroyuki,Karibe, Yusuke,Imai, Rie,Onizawa, Yuji,Yamabe, Hokuto,Iwasawa, Nobuharu
supporting information; experimental part, p. 4839 - 4848 (2011/06/21)
Tungsten(0)- and rhenium(I)-catalyzed reactions of acetylenic dienol silyl ethers based on the concept of geminal carbo-functionalization of alkynes are reported. Treatment of 3-siloxy-1,3-diene-7-ynes with catalytic amounts of [W(CO)6] or [ReCl(CO)5] under photoirradiation conditions gives synthetically useful bicyclo[3.3.0]octane derivatives in good yields. Extremely high catalytic activity is noted for the rhenium(I) complex. The reaction has been extended to substrates containing a nitrogen atom in their tethers. In this case, two kinds of synthetically useful heterocyclic compounds-the 2-azabicyclo[3.3.0]octane derivatives 9 and the monocyclic dihydropyrroles 10, with allenyl substituents-are obtained, and selective preparation of either product can be achieved through the use of an appropriate combination of the nitrogen substituent and the type of the rhenium(I) catalyst. The 2-azabicyclo[3.3.0]octane derivatives 9 are obtained selectively by carrying out treatment of N-Ns derivatives in the presence of [ReCl(CO) 4(PPh3)], whereas the dihydropyrrole derivatives 10 are obtained by treatment of N-Mbs derivatives with [ReCl(CO)5]/ AgSbF6. Finally, we have applied this geminal carbo-functionalization to one-carbon-elongated substrates containing N-Ts moieties in their tethers. Selective 5-exo cyclization is achieved in the presence of gold(I) or rhenium(I) catalysts, whereas 6-endo cyclization is observed on use of [W(CO) 6]. Geminal carbo-functionalization of 3-siloxy-1,3-dien-7-ynes leading to bicyclo[3.3.0]octane derivatives is achieved through electrophilic activation of alkynes by tungsten(0) and rhenium(I) catalysts (see graphic). Extremely high activity is noted for rhenium(I) catalysts. Furthermore, selective preparation of two different classes of heterocyclic compounds from 5-aza-3-siloxy-1,3-dien-7-ynes is also achieved by appropriate choice of the rhenium(I) catalyst and the protecting group on the nitrogen. Copyright
