Polysubstituted cyclopropanes were efficiently prepared with poly(ethylene glycol)(PEG) as soluble support. The reaction of PEG-supported pyridinium ylide with arylidenemalononitrile(R=CN) or ethyl arylidenecyan...Polysubstituted cyclopropanes were efficiently prepared with poly(ethylene glycol)(PEG) as soluble support. The reaction of PEG-supported pyridinium ylide with arylidenemalononitrile(R=CN) or ethyl arylidenecyanoa-cetate(R=COOEt) in the presence of triethylamine(TEA) afforded PEG-supported cyclopropanecarboxylates, which were cleaved by 1% KCN/EtOH to obtain polysubstituted cyclopropanes with exclusive trans-selectivity and good yields.展开更多
( 3R,4S )-4-Methyl-3-hexanol and ( 3R,4S )-4-methyl-3-heptanol, which are the pheromones of ant Tetramorium impurm and Leptogenys diminuta , were stereoselectively synthesized by six step sequence starting from N born...( 3R,4S )-4-Methyl-3-hexanol and ( 3R,4S )-4-methyl-3-heptanol, which are the pheromones of ant Tetramorium impurm and Leptogenys diminuta , were stereoselectively synthesized by six step sequence starting from N bornane 10,2 sultam separately, the two asymmetric carbon atoms of the target products were created by employing asymmetric syn aldolization of N acylbornane 10,2 sultam with propylaldehyde. The enantiomeric excess of the target products prepared by this route is over 92%.展开更多
基金Supported by the National High Technology Research and Development Program of China(No.2009AA03Z420)the Natural Science Foundation of Hubei Province of China(Nos.2007ABA031,2008CDA078)
文摘Polysubstituted cyclopropanes were efficiently prepared with poly(ethylene glycol)(PEG) as soluble support. The reaction of PEG-supported pyridinium ylide with arylidenemalononitrile(R=CN) or ethyl arylidenecyanoa-cetate(R=COOEt) in the presence of triethylamine(TEA) afforded PEG-supported cyclopropanecarboxylates, which were cleaved by 1% KCN/EtOH to obtain polysubstituted cyclopropanes with exclusive trans-selectivity and good yields.
文摘( 3R,4S )-4-Methyl-3-hexanol and ( 3R,4S )-4-methyl-3-heptanol, which are the pheromones of ant Tetramorium impurm and Leptogenys diminuta , were stereoselectively synthesized by six step sequence starting from N bornane 10,2 sultam separately, the two asymmetric carbon atoms of the target products were created by employing asymmetric syn aldolization of N acylbornane 10,2 sultam with propylaldehyde. The enantiomeric excess of the target products prepared by this route is over 92%.