NHCOCH3

C5H11

C5H11

C5H11

OHN

O

CH3

ONH

O

H3C

Reagent Solvent Temp. Time Yields

Pd(CH3CN)2Cl2 CH3CN

CH3CN

THF

DMF

DMF

NMP

NMP

DMSO

80

RT

80

RT

80

RT

80

RT

48

2

48

2

48

2

48

8

18

18

48

48

33

48

18

1 2

DMSO 80 2 17

THF 48

12

RT

2

Pd(CH3CN)2Cl2

Solvent

Pd(OAc)2

Pd(PPh3)2Cl2

PdCl2

NHCOCH3

C5H11

C5H11

C5H11

OHN

O

CH3

ONH

O

H3C

Reagent Yields(%)

DMFheat to 80oC

Pd(II)

1 2

16

19

15

NH

R

R

R

OHN

O

R'O

NHO

R'

DMF

Pd(CH3CN)2Cl2

R

1d R = Ph

Yields(%)

2d ( 35 )

R'

CH3

Ph 1e R = C5H11

1g R = Ph

2e ( 26 )

2g ( 22 )

heat to 80oCR'

O

1b R = C6H13

1c R = C7H15

1f R = C6H13

1 2

2b ( 38 )

2c ( 36 )

2f ( 24 )

NH

R

O Pd(CH3CN)2Cl2

NH

R

O

NH

O

Pd Pd

R

HNO

RPd

NHO

RPd

OHN

OO

NHO R

R

HN

OH2O

1 3 4

5

8

2

HNO

NHO

PdR R

Pd

6

HNO

NHO

PdR R

Pd

7

H2O

R

PdR

OHN

O

Synthesis of various substituted naphthalene via Palladium catalyzed Cyclization

Chia-Ying Lee b, Ming-Jung Wu a*a Faculty of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung, Taiwan.

b Graduate Institute of Pharmaceutical Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan.Tel: 886-7-3121101 ext 2220; Fax: 886-7-3125339; E-mail: mijuwu@cc.kmu.edu.tw

AbstractA novel palladium catalyzed cyclization of enediynes to give the naphthalene derivatives was reported. For instance, treatment of N-acetyl-2-(3(Z)-undecen-1,5-diynyl)anilines 1 with Pd(CH3CN)2Cl2 in DMF at 80 oC for 2h in 48 % yield.

NHR'

R

R

R

ONHR'O

R'HN

12

Pd(CH3CN)2Cl2

DMF, heat 80oC

Table 1 Reaction of 1 with Pd(CH3CN)2Cl2 in Various Solvents

Table 2 Reaction of 1 with Various Pd(II)-catalysts

Table 3 Cyclization of enediynes 1b-g

Figure 1 X-ray structure of compound 2d

Scheme 1 Proposed Mechanism for the Formation of compound 2