Cp*Ru(PN) N,O - - PowerPoint PPT Presentation

Cp*Ru(PN) 触媒による N,O - アセタ ール類の水素化反応 （ 東工大院理工） 伊藤正人○日水秋生・ 碇屋隆雄

HYDROGENATION OF POLAR BONDS WITH BIFUNCTIONAL Cp*Ru(II) CATALYSTS heterolytic cleavage of H 2 H 2 , ROH L Ru N H H H H O L = NMe 2 L R L ketones Ru Ru ROH base N N Cl H 2 H L = PPh 2 L Ru epoxides, imides N H H H A B H H 18e amine-Ru hydride A B M. Ito and T. Ikariya Chem. Commun. , 2007 , 5134

THIS WORK Ph 2 P R 1 N O Ru N R 2 R 3 Cl H 2 N,O -acetals Cp*RuCl(PN) Cp*RuCl(PN) additive R 1 N R 1 N OH O + H 2 alcohol H R 2 R 2 R 3 30 –80 °C 15 –30 atm R 3

EFFECT OF SOLVENT Cp*RuCl(PN) KO t -Bu MeN OH MeN O + H 2 solvent H 30 atm 80 °C, 18 h Ph Ph S/C = 50 solvent conv, % 0.2 M methanol >99 Ph 2 P Ru 2-propanol 33 N Cl H 2 toluene 0 Cp*RuCl(PN)

EFFECT OF ADDITIVE Cp*RuCl(PN) additive MeN OH MeN O + H 2 methanol H 15 atm 30 °C, 0.5 h Ph Ph S/C = 100 entry additive conv, % 0.2 M 1 KO t -Bu 10 2 49 3 KOTf 52 [Ph 2 NH 2 ] + [OTf] - 4 64 5 AgOTf 92

REACTION OF VARIOUS N , O -ACETALS MeN OH MeN O i -C 3 H 7 N O MeN OH i -C 3 H 7 N OH MeN O H H H Ph Ph Me Ph Ph Ph Ph Me TOF, h -1 184 86 12.5 MeN OH MeN OH C 2 H 5 N OH MeN O C 2 H 5 N O MeN O H H H n -C 6 H 13 n -C 6 H 13 Me c -C 6 H 11 Ph c -C 6 H 11 Ph Me TOF, h -1 70 >200 19 conditions: [N,O-acetal] = 0.2 M in methanol, P H 2 = 15 atm, 30 °C

EFFECT OF N -SUBSTITUENT Cp*RuCl(PN) MeO OMe AgOTf Ph OH PhN O + H 2 N + methanol H Ph 30 atm Ph 80 °C, 18 h S/C = 50 0.2 M OH Cp*RuCl(PN) N O O N AgOTf O OMe + H 2 methanol 30 atm 80 °C, 73 h S/C = 20 0.1 M

SUMMARY OTf Ph 2 Ph 2 P AgOTf P HYDROGENATION WITH CHIRAL CATALYST Ru Ru N H 2 N H 2 Cl H 2 chiral Ru Ph 2 Cp*RuCl(PN) MeN OH AgOTf MeN O P ∗ H 2 + H methanol Ru Ph 30 atm OTf Ph Me Me 30 °C, 14 h N Ph 2 Ph 2 Cl >99% H P P [ α ] D 28 = racemic –1.66° Ru Ru H chiral Ru 0.1 M, S/C = 10 (c = 1.02, CHCl 3 ) N H N H H 2 H 2 H H R 1 Me N OH R 1 N R 1 N N OH MeN OH MeN O OH O ∗ ∗ R 3 Me H H R 2 R 3 R 2 Ph Ph Me R 2 Ph R 3 Me H H racemic prochiral enantio-enriched

Me N OH H low Ph H electrophilicity MeO Ph N OH H high Ph electrophilicity H MeO

Cl Ph 2 Ph 2 P P Ru Ru N N Cl H 2 H 2 OTf Ph 2 Ph 2 P P additive Ru Ru N N Cl H 2 H 2 KOTf < [Ph 2 NH 2 ] + [OTf] - << AgOTf

+H + PhN O Ph N OH Ph N OH H H Ph Ph Ph O Me H OH OH Ph Ph N Me N Me H O O Ph H Ph Ph OH -H - MeO OMe Ph OH O N N + Me + H Ph H Ph O Me H

MeN OH MeN OH ∗ ∗ Me H Me H Ph Ph ( S )-( –)-amino alcohol [ α ] D [ α ] D 28 = 20 = –1.66° –21.6° (c = 1.02, CHCl 3 ) (c = 0.15, EtOH) V. M. Potapov, V. M. Dem'yanovich, V. I. Maleev, Zh. Org. Chem. 1985, 21, 1758.