SLIDE 1
LIGAND EFFECT: CHELATING prim-AMINE
KOt-C4H9 toluene, 30 °C OH OH [RuCl2(hmb)]2 amine ligand HS NH2 HO NH2 TsN NH2 H 7 14 76 HO NH2 HO S NH2 O O O 58 86 SN chelate ee, %
- ther
LIGAND EFFECT: CHELATING prim- AMINE OH OH [RuCl 2 (hmb)] 2 amine - - PowerPoint PPT Presentation
LIGAND EFFECT: CHELATING prim- AMINE OH OH [RuCl 2 (hmb)] 2 amine - - PowerPoint PPT Presentation
RACEMIZATION OF sec ALCOHOL CATALYZED BY Ru COMPLEXES R 1 R 1 Ru Ru H H X X R 2 R 2 N O N O H H H H Ru Ru Ph 2 P X Cl Cl NH 2 NH 2 PREVIOUS WORK THIS WORK The 85th Annual Meeting of Chemical Society of Japan, 2005,
SLIDE 2
SLIDE 3
LIGAND EFFECT: ARENE
KOt-C4H9 toluene, 30 °C OH OH [RuCl2(arene)]2 99 99 7 >99% ee 24 h S/C = 100 92 97 arene ligand ee, % arene ligand ee, % Cl Ru Ru Cl Cl Cl [RuCl2(arene)]2 Rn Rn HS(CH2)2NH2 94
SLIDE 4
REACTION OF [RuCl2(hmb)]2 WITH SN LIGAND
1/2 [RuCl2(hmb)]2 + HS NH2 R1 = 0.057 wR2 = 0.148 1.98 (s, 18H) 2.17 (s, 18H)
1H NMR (δ, CDCl3) :
P-1 (#2) + 1/2 KOt-C4H9 2-propanol 30 °C 91% yield Ru(1) –N(1) –C(14) 110.2 Bond angles (°) Ru(1) –S(2) –Ru(2) 99.7 Ru(1) –S(1) –Ru(2) 100.6 S Ru Ru S H2N NH3 Cl Cl2 – Isolation of catalyst precursor – 1/2 Ru(1) –Ru(2) 3.6790 Bond lengths (Å)
SLIDE 5
EFFECT OF STOICHIOMETRY AND REACTION CONDITIONS
[RuCl2(hmb)]2 Ru S NH2 S HS NH2 NH2 P-1 (#2) R1 = 0.120 wR2 = 0.318 Bond lengths (Å) Ru(1) –S(1) 2.383 Ru(1) –S(2) 2.409 Bond angles (°) Ru(1) –N(1) –C(14) 115.1 Ru(1) –S(2) –C(15) 113.4 Ru(1) –S(1) –C(13) 99.7
1H NMR (δ, CDCl3): 2.01(s, 18H)
Ru (excess) SN (excess) 2-propanol KOH THF CH3ONa R1 = 0.079 wR2 = 0.188 P-1 (#2) 2.27 (s, 36H)
1H NMR (δ, CDCl3):
Bond lengths (Å) Bond angles (°) Ru(1) –Ru(2) 2.7328 Ru(1) –S(1) –Ru(2) 70.51 Ru(1) –N(1) –Ru(2) 82.5 –12.3 (s, 1H) 78% yield 68% yield 30 °C 30 °C Ru Ru N H S H Cl
SLIDE 6
RACEMIZATION WITH THE Ru2(SN)2 COMPLEX
KOt-C4H9 toluene, 30 °C OH OH Ru cat Ru cat 0.5 1 1.5 2 ee, % >99 >99 2.5 1/2 [RuCl2(hmb)]2 + HSCH2CH2NH2 KOt-C4H9 / Ru 98 6 >99% ee 2 36 9 6 h S Ru Ru S H2N NH3 Cl Cl2 S/C = 100
SLIDE 7
RACEMIZATION WITH THE Ru2(SN) OR Ru(SN)2 COMPLEXES
KOt-C4H9 toluene, 30 °C OH OH Ru cat Ru cat ee, % 1/2 [RuCl2(hmb)]2 + HSCH2CH2NH2 KOt-C4H9 / Ru Ru S NH2 S NH2 2 7 99 83 97 98 low reactivity >99% ee 2 7 24h Ru Ru N H S H Cl Ru2(SN) Ru(SN)2 S/C = 100
SLIDE 8
S Ru Ru S NH2 H2N Cl2
POSSIBLE MECHANISM
HS NH2 Cl Ru Ru Cl Cl Cl base 16e 18e Ru S NH S Ru Ru S NH HN S Ru Ru S H2N NH3 Cl Cl2 ESI-MS: m/z 340[M+H]+ C14H23N1S1Ru1 Ru S NH2 H R1 R2 OH R1 R2 OH R1 R2 O R1 R2 O base base
SLIDE 9
KOt-C4H9 (1.5 mol%) toluene, 30 °C OH OH Ru cat (0.5 mol%)
SUMMARY
6% ee Racemization of sec-alcohols catalyzed by RuSN(hmb) complexes Isolation of catalyst precursors (hmb)Ru complexes with SN ligand 6 h Ru cat >99% ee S Ru Ru S H2N NH3 Cl Cl2 Ru2(SN) Ru(SN)2 Ru2(SN)2
SLIDE 10