The Ru-3(CO)(12)/1,10-phenanthroline-catalyzed hydroformylation of styrene
under 100 atm of syngas (CO:H-2 = 1:1) at 120 degrees C in DMF gives the co
rresponding branched and linear aldehydes in 58 and 22% yields, respectivel
y. With the use of quinuclidine as a ligand in place of 1,10-phenanthroline
in N,N-dimethylacetamide, the corresponding branched and linear ore-alcoho
ls were obtained in 53 and 28% yields, respectively. Hydroformylation of me
thyl acrylate by a catalyst system of Ru-3(CO)(12)/1,10-phenanthroline to a
fford 4-methoxy-4-methyl-delta-valerolactone lin 31% yield, while the catal
yst system of Ru-3(CO)(12)/PPh3 yields the open-chain aldehyde, dimethyl 2-
formyl-2-methylglularate (3), which is the precursor of lactone 1 in 18% yi
eld. (C) 1999 Elsevier Science B.V. All rights reserved.