Palladium catalysed queuing processes. Part 1: Termolecular cyclization–anion capture employing carbon monoxide as a relay switch and hydride, organotin(IV) or boron reagents
作者:Stephen Brown、Stephen Clarkson、Ronald Grigg、W.Anthony Thomas、Visuvanathar Sridharan、D.M Wilson
DOI:10.1016/s0040-4020(00)01103-0
日期:2001.2
enhance the scope of our cyclization–anion capture methodology, is introduced and exemplified by a wide variety of catalytic cyclization–carbonylation–anion capture processes employing hydride, organostannanes and NaBPh4 as anion capture agents. Mono- and bis-cyclization processes forming 5- and 6-membered rings are described, all of which employ CO at atmospheric pressure. Cyclocarboformylation processes
Three component palladium catalysed cyclisation-carbonylation-anion capture processes
作者:Ronald Grigg、James Redpath、Visuvanathar Sridharan、David Wilson
DOI:10.1016/s0040-4039(00)73376-4
日期:1994.6
A series of palladiumcatalysed three component cyclisation-carbonylation-anion capture processes involving aryl iodides, carbon monoxide (1 atm) and Sn(IV)R or B(III)R reagents are reported. The stereo- and regio-specific cascade processes furnish tetrasubstituted carbon centres and fused- and spirocyclic-rings in excellent yield.
A range of δ- and σ-alkenyl aryl- and vinyl- halides undergo palladiumcatalysed cyclisation with subsequent transfer of cyanide ion in the presence of potassium cyanide (1.2mol) and 10mol % 18-crown-6.
Palladium catalysed tandem cyclisation-anion capture processes. Part 3. Organoboron anion transfer agents
作者:Ronald Grigg、JoséM. Sansano、Vijayaratnam Santhakumar、Visuvanathar Sridharan、Ravishanker Thangavelanthum、Mark Thornton-Pett、David Wilson
DOI:10.1016/s0040-4020(97)00754-0
日期:1997.8
The cyclisation-anion capture protocol has been applied to a wide range of starter and terminating species to effect regio-and stereo-specific mono-and bis-cyclisation processes in which a variety of organoboronderivatives function as anion transfer reagents. Direct capture (no cyclisation) is rarely a problem and it can usually be suppressed by modification of the reaction conditions. (C) 1997 Elsevier Science Ltd.
The addition of TlOAc (3 mol) promotes a series of cylisation-carbonylation reactions under 1 atm of CO at 65-degrees-C. One example of a bis-cyclisation is reported.