The Diels-Alder Reaction

M

H

O

O

O

+

O

Ph O H

R1

R

O

55

R

O

O

R

PhMe, Rfx

+

! "

15−20 h, 31−57%

O

O

E

E

R

R

R

E

E

E

+

PhH or PhMe

+

E

E! "

100−200 C

+

E

20−24 h, 30−88%

E

E

E

E

M

OSMT

O

+

THF, 140 C, 140 h, 75%

CFOMe

H3O

CF

! "

or 15 kbar, 80%

3

80%

3

OSMT

58

59

NO2

NMe2

H

R

PhMe, Rfx

+

! "

8 h, 26−71% R

NO2

60

NMe2

61

62

M

RO

OR

63

64

65

66

M

O

[63]

H

H

H

O

H

+

H

+

H

H

O

H

O

H

3

1

2

2

1

M

O

O

CCl4, Rfx, 75%

+

68

O

O

H

H triglyme, Rfx, 60 h

Pd/C

MeO

O

O

[65]

O

H O

H O

[66]

O

H

H

[66]

OMe O

MeO

O

69

MeO

O

MeO

OMe

O

O

[66]

O

[67]

O

O

H

O

O +

O

H

O

O

MeO

MeO

M

O

O

+

1. Et3N, Rfx, 6 h, 43%

+

! "

2. Pd/C, 53%

O

Br

O

H

H

R H

R

1.

, DME

CCl4, Rfx, 48 h, 50%

2. DDQ

R1

71

i) NaBH4

DCM/MeOH,

overall yield: 42%

160

C, 24 h

ii) Pd/C

R1 = H, Ph

53%

M

O

1.

, DME

1. PhMe, Rfx,

2. DDQ, PhH,

20 h

Rfx, 16 h

O

2. DDQ, PhH,

72

overall yield: 30%

Rfx, 5 h

O

overall yield: 37%

Y

Y

X

X

X

OSMT

73 a, X = O

Y

Y

b, X = S

74, X = O

75, X = S

Y

Y : dienophile

M

E

E

CN

DDQ

R

R

R

73%

O

R2

O

O

R

R2

2

CN

R1

R1

CN

R1

R

E

140 C,

18 h,

R = R1 = H

O

R2

62%

R = R1 = H, R2 = NO2

R2 = CO2Et

R1

140 C, 40 h

85% DDQ

73%

CN

CN

E

E

, 140 C, 48 h, 57%

R2

, 140 C, 40 h, 53%

R

R

O

R

R = R1 = H, R2 = CO2Et

R = R

= H, R

= NO

O

R

R1

1

2

2

O

2

R1

E

73

E

R1

E

E

xylene, Rfx,

R = R1 = R2 = H

PhH, 80 ˚C,

R1 = R2 = H

24 h, 40%

24 h, 5%

R =p-NO2C6H4

E

E

E

E

R

R

O

R2

O

R2

R1

E = CO2Me

R1

M