TY - JOUR
T1 - "Widening the roof"
T2 - Synthesis and characterization of new chiral C1-symmetric octahydrofluorenyl organolanthanide catalysts and their implementation in the stereoselective cyclizations of aminoalkenes and phosphinoalkenes
AU - Douglass, Michael R.
AU - Ogasawara, Masamichi
AU - Hong, Sukwon
AU - Metz, Matthew V.
AU - Marks, Tobin J
PY - 2002/2/4
Y1 - 2002/2/4
N2 - New chiral C1-symmetric organolanthanide catalysts of the type Me2Si(OHF)(CpR*)LnN-(TMS)2 (OHF = η5-octahydrofluoreny]; Cp = η5-C5H3; R* = (-)-menthyl; Ln = Sm, Y, Lu; TMS = SiMe3) have been synthesized, characterized, and implemented in the enantioselective and diastereoselective cyclizations of aminoalkenes and phosphinoalkenes. Me2Si(OHF)(CpR*)LnCl2
-Li(DME)2 + catalyst precursors can be prepared in up to ∼90% diastereomeric purity and then converted into the corresponding amido catalysts, which can be isolated in ∼100% diastereomeric purity after recrystallization. The catalyst (S)-Me2Si(OHF)(CpR*)YN(TMS)2 has been crystallographically characterized. The activity of these catalysts for the hydroamination/cyclization of aminoalkenes and for the hydrophosphination/cyclization of phosphinoalkenes is described. Enantioselectivites as high as 67% are obtained in hydroamination, and diastereoselectivities of as high as 96% are obtained in hydrophosphination.
AB - New chiral C1-symmetric organolanthanide catalysts of the type Me2Si(OHF)(CpR*)LnN-(TMS)2 (OHF = η5-octahydrofluoreny]; Cp = η5-C5H3; R* = (-)-menthyl; Ln = Sm, Y, Lu; TMS = SiMe3) have been synthesized, characterized, and implemented in the enantioselective and diastereoselective cyclizations of aminoalkenes and phosphinoalkenes. Me2Si(OHF)(CpR*)LnCl2
-Li(DME)2 + catalyst precursors can be prepared in up to ∼90% diastereomeric purity and then converted into the corresponding amido catalysts, which can be isolated in ∼100% diastereomeric purity after recrystallization. The catalyst (S)-Me2Si(OHF)(CpR*)YN(TMS)2 has been crystallographically characterized. The activity of these catalysts for the hydroamination/cyclization of aminoalkenes and for the hydrophosphination/cyclization of phosphinoalkenes is described. Enantioselectivites as high as 67% are obtained in hydroamination, and diastereoselectivities of as high as 96% are obtained in hydrophosphination.
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U2 - 10.1021/om0104013
DO - 10.1021/om0104013
M3 - Article
AN - SCOPUS:0000988919
VL - 21
SP - 283
EP - 292
JO - Organometallics
JF - Organometallics
SN - 0276-7333
IS - 2
ER -