有机化学习题福山组会题2007年05

05/02/2007

1

OOOMeOMe1) p-TsOH·H2O MeNO2

70 °C, 90%2) DIBAL, toluene –78 °C, 100%3) BF3·OEt2

MeCN, 0 °C, 99%

tricyclic

compound

RuCl3·nH2ONaIO4MeCN-CCl4

0 °C

HO2COCO2H

S. Nagumo et al., Tetrahedron Lett., 43, 5333 (2002)

O2

H2NOHNCO2H* theoretical amount

SNaNO2 (3 eq)* , HCl

MeOH

MeOSNH

O3

Me

OHC

O

Me1) TMSC(Li)N2,THF –78 °C to rt, 71%2) Bu3SnCu(Bu)CNLi2 THF, –78 °C; MeI, DMPU –78 °C to rt3) I2, Et2O, 0 °C 80% (2 steps)

C11H17IO

R. J. Stoodley et al., Tetrahedron Lett., 10, 941 (1967)1) vinyl magnesium bromide Pd(PPh3)4, PhH, 70 °C 88%2) H2, CO, Rh(acac)(CO)2 (S, R)-BINAPHOS PhH, 30-35 °C, 20 atm3) CrCl2, CHI3, THF 72% (2 steps)

Me

I

MeMeO

MeE. N. Jacobsen et al., J. Am. Chem. Soc., 123, 10772 (2001)

4

HNN(as 4 eq)

96%

thionyl chloride(theoretically 1 eq)

CH2Cl2,–10 °C to rt;

filtration;

Me

NH2

MgBr

(1 eq)THF96%

toluenereflux51%

Me

NH

Kim, Y. H. et al. Tetrahedron Lett. 26, 3821 (1995)Julia, S. A. et al. Tetrahedron Lett. 27, 837 (1996)

5

1) benzene reflux, quant

C12H18O4

1) MeLi (1.05 eq) THF, –78 °C; TFAA, 82%2)LiOMeTHF, MW120 °C;DMPCH2Cl2, 0 °C75%OOt-BuOOMe

t-BuOOt-Bu

C10H18O2

2) NBS, CCl4 83%

, THF 37% (dr = 3:2)F. Serratosa, Acc. Chem. Res., 16, 170 (1983)

D. C. Harrowven et al., Angew. Chem. Int. Ed., 46, 425 (2007)

Fukuyama Group - Group Meeting Problems

05/12/2007

1

MeOOCBocNS1)

COOMeNN 105 ºC, 45hMeOOC2) Pb(OAc)4 (2.2 eq), benzene, reflux3) NaOAc, MeOH

MeOOCBocNOHSR. B. Woodward et al., J. Am. Chem. Soc., 88, 852 (1966)

2

MeH󰀁NHNC1) t-BuOCl (1.2 equiv) CH2Cl2, –78 °C;

prenyl 9-BBN (2 equiv) –78 °C 60%

2) hυ, Et3N (xs) PhH, rt 41%

(63% based on RSM)

MeH󰀁NHNCprenyl 9-BBN:BP. S. Baran et al., Nature, 446, 404 (2007)

3

C8H8O3isovanillin

1) allyl bromide K2CO3, acetone reflux, 8 h, 92%2) 180º C, decalin 5 h, 95%3) MeI, K2CO3 acetone, reflux 8 h, 83%

C12H14O3

4) acrylonitrile, DABCO H2O, rt 3-5 days 67%

5) Grubbs' 2nd gen. (5 mol%) 0.05 M CH2Cl2, rt 5-8 h, 90%

OCH3

H3CO

CN

E. Wang et al., Tetrahedron, 63, 2824 (2007)

4

OTBSOHOH1) iBuO2CCl Et3N, Et2O; CH2N2, Et2O 0 °C to rt, 81%

OH2) Cu(CF3COCHCOCF3)2

CH2Cl2, reflux, 96%

bicycliccompound1) PhNTf2 NaHMDS THF, –78 °C

2) CH2=C(OEt)SnBu3 Pd(PPh3)4, LiCl THF, reflux3) methyl vinyl ketone toluene, reflux 67% (3 steps)

EtOHOHHOTBSOJ. S. Clark et al., Angew. Chem. Int. Ed., 46, 437 (2007)

5

MeO

MeOnBu

1) Mg

Br(CH2)2Br,Br THF, 1.5 h, 92%

OO3) NH2NH2, KOH,HO HO(CH2)2OH

110 to 190 °C, 8 h4) O3, EtOAc, –78 °C, 4 h; PPh3, overnight 51% (2 steps)

OH

HOHOH2) TsOH, acetone, reflux 11 h, 82%

nBu

D. Kim et al., J. Org. Chem., 65, 4846 (2000)

Fukuyama Group - Group Meeting Problems

05/30/2007

1

BrPh3PCH3

O󰀁n-BuLi (1 eq)THF0 °C to rt;n-BuLi (1 eq)cyclohexanone−23 °C to rt56%C11H18OKH (1.3 eq)18-crown-6THF, reflux76%CHOE. J. Enholm et al., J. Org. Chem., 55, 324 (1990)

2

PhSO+OMeOHTFAA (1.5 eq)CH3CN−40 ºC83%MeY. Kita et al., Org. Lett., 2, 2279 (2000)C23H20O4SOMe1) mCPBA (1 eq) 98%2) n-BuLi (5 eq) THF, −78 ºC; DMF (5 eq) 56%OHCOOMeOOO3

ON3BF3⋅OEt2, O2–78 to 0 ºC40%tetracyclic compoundC12H17NO3H2, Pd/CTHF77%HOONHHF. G. West et al., Org. Lett., 9, 703 (2007)4

OCHOOMeMeNHOHDMADrt85%PhMe, reflux50%OMeHNCO2MeCO2MeHMe5

PhI(OAc)2 (1.5 eq)I2 (1.0 eq), hνbenzene1) conc. HCl dioxane, 40 °C2) (COCl)2, cat. DMF benzeneS. Kanemasa et al., Chem. Lett., 797 (1984)NOHBzOSOOHCNPy, DMAP, O2toluene, 80 °C;P(OMe)3BzOOOOHS. Hatakeyama et al., J. Am. Chem. Soc., 116, 4081 (1994)