New carbonylation reaction of tungsten-propargyl compounds via protonation at a prolonged period
Journal
Organometallics
Journal Volume
18
Journal Issue
4
Pages
748-752
Date Issued
1999
Author(s)
Abstract
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-CH2CHCHR−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-CH2C⋮CPh) (9), its reactions with triflic acid and water in the same reaction sequence produce (C5Me5)W(CO)2(η1,η2-CH2CHCHPh−O−CO−) as two diastereomers which undergo mutual exchange according to variable-temperature 1H NMR spectroscopy.
SDGs
Type
journal article