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

18e amine-Ru hydride H2, ROH A B A B H H base L = NMe2 ketones L = PPh2 epoxides, imides ROH heterolytic cleavage of H2 Ru N H2 Cl L Ru N H L H H O H R Ru N L H Ru N H L H H

• M. Ito and T. Ikariya Chem. Commun., 2007, 5134

Cp*RuCl(PN) + H2 15 –30 atm alcohol 30 –80 °C additive Cp*RuCl(PN)

THIS WORK

R1N O N,O-acetals R2 R3 Ru Cl Ph2 P N H2 R1N O R2 R3 R1N H OH R3 R2

solvent conv, % methanol 2-propanol toluene >99 33 Cp*RuCl(PN) + H2 MeN O Ph 30 atm solvent MeN H OH Ph S/C = 50 0.2 M 80 °C, 18 h KOt-Bu

EFFECT OF SOLVENT

Cp*RuCl(PN) Ru Cl Ph2 P N H2

conv, % 49 additive Cp*RuCl(PN) + H2

EFFECT OF ADDITIVE

MeN O Ph 92 AgOTf KOt-Bu 10 15 atm methanol MeN H OH Ph S/C = 100 0.2 M additive 30 °C, 0.5 h KOTf 52 [Ph2NH2]+[OTf]- 64 entry 1 2 3 4 5

MeN O MeN O Ph c-C6H11 MeN O Ph Me MeN O n-C6H13 Me C2H5N O i-C3H7N O Ph Ph 184 TOF, h-1 TOF, h-1 MeN H OH Ph 70 C2H5N H OH Ph 86 i-C3H7N H OH Ph >200 MeN H OH c-C6H11 12.5 19 MeN H OH Me Ph MeN H OH Me n-C6H13

REACTION OF VARIOUS N,O-ACETALS

conditions: [N,O-acetal] = 0.2 M in methanol, PH2 = 15 atm, 30 °C

Cp*RuCl(PN) + H2 methanol 80 °C, 18 h S/C = 50 0.2 M AgOTf 30 atm PhN O Ph Ph MeO OMe + Ph N H OH Cp*RuCl(PN) AgOTf + H2 methanol 80 °C, 73 h N O O N O OH OMe 30 atm S/C = 20 0.1 M

EFFECT OF N-SUBSTITUENT

chiral Ru + H2 methanol 30 °C, 14 h MeN O Ph Me >99%

HYDROGENATION WITH CHIRAL CATALYST

[α]D

28 =

–1.66° (c = 1.02, CHCl3) racemic chiral Ru 30 atm MeN O Ph Me H prochiral enantio-enriched racemic H MeN

∗

H OH Me Ph N OH Ph Me Me AgOTf 0.1 M, S/C = 10 Ru Cl Ph2 P N H MeN

∗

H OH Me Ph R1N O R2 R3 H H R1N

∗

H OH R3 R2 N OH R2 R3 R1 Ru N H2 H Ph2 P Ru N H2 Ph2 P H H OTf Ru N H2 Ph2 P OTf

SUMMARY

H2 AgOTf Ru N H2 Cl Ph2 P Cp*RuCl(PN)

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

Ru N H2 Cl Ph2 P Ru N H2 Ph2 P Ru N H2 Cl Ph2 P Ru N H2 Ph2 P OTf Cl additive KOTf < [Ph2NH2]+[OTf]- << AgOTf

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

• H-

[α]D

28 =

–1.66° (c = 1.02, CHCl3) MeN

∗

H OH Ph Me MeN

∗

H OH Ph Me

• V. M. Potapov, V. M. Dem'yanovich, V. I. Maleev, Zh. Org. Chem. 1985, 21, 1758.

(S)-( –)-amino alcohol [α]D

20 =

–21.6° (c = 0.15, EtOH)