220886-25-9Relevant academic research and scientific papers
New carbonylation reaction of tungsten-propargyl compounds via protonation at a prolonged period
Madhushaw, Reniguntala J.,Cheruku, Srinivasa Rao,Narkunan, Kesavaram,Lee, Gene-Hsian,Peng, Shie-Ming,Liu, Rai-Shung
, p. 748 - 752 (2008/10/08)
The CpW(CO)3(η1-CH2C=CR) (R = Me 1, Ph 2) complexes were treated with triflic acid (2.0 equiv) in cold dichloromethane (-78°C), and after a long period to the mixture was added water or RNH2 to give good yields of carbonylation products CpW(CO)2(η1,η2-CH 2-CHCHR-Y-CO-) (R = Me, Ph; Y = RN, O). These products were fully characterized by appropriate physical methods including single-crystal X-ray diffraction. If a chiral amine such as (R)-methylbenzylamine was used in the reaction, two optically active isomers in equal proportions were obtained and further separated on a silica column. In the case of (C5Me5)W(CO)3(η1-CH 2C=CPh) (9), its reactions with triflic acid and water in the same reaction sequence produce (C5Me5)W(CO)2(η1,η 2-CH2CHCHPh-O-CO-) as two diastereomers which undergo mutual exchange according to variable-temperature 1H NMR spectroscopy.
