Amination reactions hgand synthesis

Another reaction for the synthesis of pyrroles 37 was reported using ruthenium catalysis in PEG-400 without the use of external hgands. Ketones 34, amines 35, and ethylene glycol 36 were the simple starting materials and the... 

Apart from this special behavior, a reliable protection of the phosphine group during synthesis and storage can be achieved by adduct formation with BH3. Several methods are described in the literature to remove the BHj group before the catalytic reaction by the reaction of amines or acids [162]. Moreover, under hydroformylation conditions, CO can successfully compete with the phosphine for BH3 and thus initiate the breakage of the P-B bond [163]. Phosphine hgands generated in this manner from phosphine borane adducts did not differ in the catalytic properties observed with phosphines directly submitted to the catalyst formation. 

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