Metódy prípravy benzoxazolov

N

OR

Y1

Y2

Y3

Y4

NH2

OH

Y1

Y2

Y3

Y4

R

HO

O

R

Cl

O

R

H

O

+ R

H3CS

N

R

R1O

R3O

R2O

R

H

HNN

OR

N

OHR

H

RX

X

X

+ oxidáciaH

HO R H2N R + oxidácia

R

R1O

O

Chen, T.-R. J. Organomet. Chem. 2008, 693, 3117–3130.Wena, X.; El Bakali, J.; Deprez-Poulain, R.; Deprez, B. Tetrahedron Lett. 2012, 53, 2440–2443.

R

ONH2

OH

T3P, DIPEA

EtOAc, MW160°C, 15 min

+HO

N

OR

R4-ClPh4-MePhPh4-pyCH2CH2-4-ClPh

95%73%76%93%91%

P

OP

O

PO

O

Pr

Pr

O

O Pr

R1 R2HClH

HHCl

70%65%55%

NH2

OH

O

HO

N

O+

PPA

200°C, 5 hR1

R2 R2

R1

T3P - anhydrid kyseliny propánfosfónovej

Phillipsova kondenzácia

Wang, Y.; Sarris, K.; Sauer, D. R.; Djuric, S. W. Tetrahedron Letters 2006, 47, 4823–4826.

PhHO

O

OH

NH2

+

PS-PPh3 (3 eq)CCl3CN (2 eq)

MW, CH3CN, 150°C, 15 min

N

O97%

OH

HNO

Ph

N

OPh 97%

N

OPh

Cl94%

N

OPh

NO2

79%N

O N

S94%

N

O

PhCl93%

N

OPh 89%

Kangani, C. O.; Kelleya, D. E.; Day, B. W. Tetrahedron Lett. 2006, 47, 6497–6499.

iPr2NEt, K2CO3Deoxo-Fluor

CH2Cl2, 0°C, 2 h

NH2

OHX

R

HO

O

+

N

OR

X

C15H31trans-C18H33cis-C18H33

Ph4-NO2Ph4-CH3Ph

X = H X = NO2R99%98%97%99%98%95%

98%97%98%98%98%98%

H3CON

OCH3

SF3

Deoxo-Fluor – fluoračné činidlo

NBocNH

OOH

NBoc

O

NDIAD, PPh3

THF, 60°C, 5h

86%

NNCNEt .HCl N

NN

HO

NN

O

OO

O

Kudo, Y.; Suzuki, M.; Suemoto, T.; Okamura, N.; Shiomitsu, T.; Shimazu, H. US Patent 0 018 825 A1, 2006.

NBoc

HOOCNH2

OH

EDC.HClHOBTDMSO, RT

+

EDC.HCl1-etyl-3-(3-dimetylaminopropyl)

karbodiimid hydrochlorid

HOBT1-hydroxybenzotriazol

DIADdiizopropylazodikarboxylát

Kawashita, Y.; Nakamichi, N.; Kawabata, H.; Hayashi, M. Org. Lett. 2003, 5, 3713-3715.

ONH2

OH

O2, Darco KB (50 wt%)

xylen, 120°C, 3 h+

H

N

O

R2

R1

N

OHR1

R2

R2

R1

R1O

NHR2

R1HH.HHH

R2H.CH3OCH3ClNO2

78%.79%76%88%86%

CH3NO2NO2NO2

HHOCH3Cl

82%82% (24 h)67% (29 h)83% (21 h)

R1 R2

Qiao, J. X.; Wang, T. C.; Hu, C.; Li, J.; Wexler, R. R.; Lam P. Y. S. Org. Lett., 2011, 13, 1804-1807.Schrage, K. (Dynamit Nobel AG) US Patent 4 107 169, 1978.

X NH2.HCl

OH180°CCl3C+

R1

R2

X N

O

R1

R2

F3CX

NH2

OH+

X

N

O

HO

X: CH, N

HO

X: CH, 94% N, 68%

1M NaOH

N

SF3C

NH2NH2

OH X

N

O

N

S

NH2

45%

80°C, 2 h

80°C, 24 h

1M NaOH

NH

NHO

OF3CNH

NHO

ON

O 98%

1M NaOH80°C, 2 h

+

NH2

OH+

R2R1 XH.HCH3Cl

H.HHH

CH.NCHCH

75%.46%67%78%

NO2Ph.COOCH3H

HHHNO2

CH.CHCHCH

58%.48%32%57%

R2R1 X

NH2

OH

R

CH3EtO

OEt

OEt

N

OCH3

R+

DBDMH (2 mol%)

R: HClMe

R: HClMe

95%85%98%RT, 2 min

NN

O

OBr

Br

Hojati, S. F.; Maleki, B.; Beykzadeh, Z. Monatsh. Chem. 2011, 142, 87-91.Bastug, G.; Eviolitte, C.; Markó, I. E. Org. Lett. 2012, 14, 3502-3505.

R CN

1) R1OH, AcCl2) R2OH, CH2Cl2 R

OR1

R2O OR2

NH2

OH

R

R: HClMe

EtO

OO

EtO

OO

Cl

+N

O

N

OCl

BF3.OEt2 (1 eq)

CH2Cl2, RT, 3h

R: HClMe

R: HClMe

82%95%80%

95%88%80%

DBDMH2,4-dibróm-5,5-

dimetylhydantoínPinnerova reakcia

OH HO COClClOC

ClOC COCl

NH2

OH

OH HO COOCH3H3COOC

H3COOC COOCH3

PCl3sulfolan

OH HOO

O O

OHN

HN

HN

HN

OH

HO

OH HON

O NO

NON

OHO

OH

96%

120-140°C, 24 h

Ueno, R.; Kitayama, M.; Minami, K.; Wakamori, H. EP 1 380 564 A1, 2004.

Jiao, P.; Xu, J.; Zhang, Q.; Choib, M. C. K.; Chan, A. S. C. Tetrahedron: Asymmetry 2001, 12, 3081–3088.

OO

OCl

OCl

NH2

OH

R1

R2

OO

OHN

ONH

OH HO

R2

R1

R2

R1

+

OO

NO O

N

R1R2

R1R2

THF, RT, 1 h

PPh3 (2.2 eq)DEAD (2.2 eq)

THF, RT, 8 h H.MeClNO2Cl

H.HHHNO2

R1 R2

78%.99%75%62%52%Et

O NN O

O

O

Et

DEADdietylazodikarboxylát

NH2

OH H

O+

Ni-SiO2 (20 mol%)

EtOH, RT, 1.5h

N

OR1

R2

R1

R2

Me.MeMeOHFCF3Cl

Me.HHHHHH

98%.96%94%93%89% (2.5 h)86% (3 h)88% (2.5 h)

R1 R2

Madilla, S.; Jonnalagadda, S. B. J. Chil. Chem. Soc. 2012, 57, 1099-1100.Praveen, C.; Nandakumar, A.; Dheenkumar, P.; Muralidharan, D.; Perumal, P. T. J. Chem. Sci. 2012, 124, 609–624.

NH2

OH

ArO

H

N

OHH

Ar N

OAr+

PIFA (1.05 eq)

N

OAr

H

IOPh

CF3OPh

IOO

O

F3C

O

CF3

N

O

Ar

H

H

- PhI- CF3COOH

- CF3COOH

EtOHMW, 80°C, 15 min

IOO

O

F3C

O

CF3

PIFAbis(trifluoracetoxy)jodob

enzén

Blacker, A. J.; Farah, M. M.; Marsden, S. P.; Saidi, O.; Williams, J. M. J. Tetrahedron Lett. 2009, 50, 6106–6109.Xiao, T.; Xiong, S.; Xie, Y.; Donga, X.; Zhou, L. RSC Adv. 2013, 3, 15592–15595.

Ph4-MeOPh4-MePh4-ClPhPh4-MeOPh4-MeOPh4-MePh4-MePhPh

HHHHHHHHHMe

HHHHMeMeClMeClH

43%70%62%36%64%68%50%68%42%52%

R1 R2 R3

H2N R1

NH2

OHHN R1

R2R3

N

O

R2

R3

R1

N

OH

R1R3

R2[Ru] cat. (1 mol%)DMBQ (2 eq)mezitylén150°C, 24 h

O

O

H3CO OCH3

Ph

PhPh

Ph

O

Ru

Ph

PhPh

Ph

O

RuOCOC

COCO

H

H

DMBQ2,6-dimetoxybenzochinón

[Ru] cat.Shvoov katalyzátor

EtOH, RT, 24 h

NH2

OH H

O+

NiO-SiO2N

OH68%

H2N COOH(CF3CO)2O (2.3 eq)

CF3COOH, 0°C, 2 hHN COOH

CF3

O

98%

HN COOH

CF3

O MeI, K2CO3

DMF N COOH

CF3

O