Formation and photochemical isomerization of arylated 1,3-dihydro-2H-azepin-2-ones

Tetrahedron

Letters

FOmlATION

No. 20, pp 1705 - 1708,

ANC EHOTOCHEMICAL

ISOMEBIZATICN

Hans-Dieter Depdrtment

of Crganlc Tlnlverslty

(Received we have

solulmr~)

for

publlcatlon

one-step

(L-2) whlcn,

synthesis

(150 ml)

of splroqLlno1 of methyleqe

loilowed

crystalline

evdpordtlon

1976)

of drylated

t-r4H9,

metka,iol and

and

1,3-dlhydro-2H-

4.08

g,

gives

rn

IO mmol) (40%

metkyiamlne

of solvent

obtalned

in

aqueous

XI 87% yield B

preclpltate

R3 + tiN/

R4= H m__c

-

'RL

d2 1-3 -For

5 Apral

are easily 1 nl?c,lol,

ether 1 (a'= a2=

chloride,

by pdrtldl

Brltaln.

Swede?

1x1 tuzn,

roup'lcg: of 2,4-dl-slbstzt,jted

a solutlon

2 hr,

for

etkers

by oxldatlve

of 'PPrhnology

20 Gothenburg,

iunple

high yield

as coiorless

S-402

accepted

in Great

Gustafsson

-J?nven1ty

spLroqulnol

(-5) from

Refluxlng

1976,

Kenneth

rhalmers

of cothepburg,

Prmted

CE AKYLA'rfil l,j-7IW3RO-2H-AZEPIN-~-ONES

a remarkably

weplnones

a 1 1 1 m-xture

Pergaaon Press.

Becker*and

rhemlstry,

1x1UK 22 Match

found

1976.

R’- !2

4 see

Table

1

1705

R’

R2

No.

20

K3Fe(CN)6 R2

R2

-

IS'= R2=

--5a-5c

s,

-

t-C4H9

5,

h3

h3 I

I

R2

acetone -6a

h-2

Table

I. Azepuux~es

Compound

2 and ,, and their

R'

-2

PhotoIsomers

R5

162-164

76

c-L6Hll

209-211

75

IH

144-146

72

n-C3H_/

180-182

El

n-CjH/

211-214

90

c-C6HIl

188-l 91

86

CH

167-168

57

r-CJH7

190-193

78

L-C~H?,

237-238

97

130-143

66

WCjYi

133-153

93

‘-C6H1 1

138-155

83

203-205

72

136-138

71

181-183

95

t-C4H9

t-C4<9 t-c489

t-C5H,, t-r4HY

tFh

t-C4HS

CFh

7 5

CE L

1

?

R = 1, = t-C4k9

Yield

n-C31?

CH

t-C5"11

mp ('C)

87

t-L4H9

t-C,9, 4 i t-r?“, 1

1 and i

153-155

t-C4H9

t-c4119

9

3

3

3

3

CH 7 35 c-C6H11

($)

170?

No. 20

data ' Oxldatlon

of -8a with KMnO

substituted

2(3H)-benzofuranone

2 ( mp 234-235

veals

carbonyl

spectroscopic

three

benzofuranone

absorption

n-Propylamlne the same manner as well

photochemlcal

qulnol

opening

with

In support qulnol

ethers

a suspenszon mln gives

ring

yellow

ana spectroscopic. that had been

had been

In summary, qulnonold tlon.

solution

at rool temperatare

compound

however,

data

obtained

coupling assIgned.

Jugated

dlene

(RI= t-C4H9,

e

of primary

adnlnes to splro-

of

X2= CPhS), involves

2,4-

for the reactlon reaction

that secondary

amznes

2,4-cyclohexadie~,ones. (53 ml)

nucleophlllc

a &amlno-substituted

to the followlng

In methanol

smooth

1). Azeplnones

according

from which

and 2

(see Table

2 probably

to give

found

ether 1 an J&

and -6c underwent

by Paquette

we have

splroqulnol azeplnones

suggested

For

sequence.

react

example,

and morphollne

4 (a'= R2= t-C4HY,

of chlor-

with

splro

refluxlng

(5 ml) for 5

R3- R4= CH2CH20CH2CH2)

(94s yield), Its structure is supported by elemental 10 this substance ~5 lderltlcal with a lnterestlngly, previously

of primary

to give

and extends

moiety

re-

2(3H)-

11, tne cuprous

chloride-morphollne

to which

different

complex

structures,

11

In atidltlon, the observed

2 and 5 confirms

products

of 2,4-dl-t-butylphenoi,

the reactlon

equivalents,

with

by addltlon

in 1-J by the amIne

of I (4.08 g, IO mmol)

oxldatlve

spectrum

to react

of azep_nones

6-amino-substituted

analysis

catalyzed

and j8

of this mechanism,

a bright

crystallizes

C5H,,)

as orlglnally 9 ion, lsomerlzes

to give

the splro-

the characterlstlc

and the resulting

oxldatlon

which,

phenolate

found

In good yields

for the formatIon

of the oxetene

gives 13C NMR

exhlblts

to give 1 and ;, respectively

obtained

2 (R'= R*=

cyclohexadlenone amine

were

for methylamlne

lsomerlaatlon

The mechanism

whose

at 5.5 P.~

and cyclohexylnmlne

also

, 92$ yield)

IR spectrum

benzofurano-annelated

2 were

ethers

and whose

as described

as their

structure

groups

at room temperature 4

amInes

with

spl~oqulnol

?,3-dlhydro-2H-azeplnones smooth

photochemlcal

the previously

in T-membered

noted

heterocyrllc

ethers,

appears

to be a general

lsomerlzatlon

excited

compounds

*Late 12

or their

ortho reac-

of the azeplnones

leactlvlty

of the con-

No. 20

References and Notes

1.

a) V.V. Karpov and M.L. Khldekel, Zhur.org+Khlm , 4, b)

2.

A.S

2

Calcd

for

IR (KB~) J=

3.

861

2.5

C29

He, I),

5 62

(d,

J=

1.32

(s,

91,

(d,

kiz,

1.23

I),

(~3

2.5

J= 2.87

Yz,

1655,

(s,

:);

1625

6.43

3),

1 ‘9 (b,

Y),

1969).

C,79.22, H, 10.32. Pound

(broad), 1680,

7.03

6.5

(439.68)

H45 NO 2

3370

3520,

(1968)

31,

BTayand H.-D. Becker, us Patent 1,900,680 (July

2.31

at-‘.

(d, (br

J-1 d,

79.33,

C,

NW? (CDC13, Ez,

J-

1);

6.5

6

5.68

Hz,

11,

H, mm)

lo.36 7.38

(d,

1 OH);

(s, 1.45

(s,

Y),

9)

This type of lntramolecklar ox_dative coupling of a phenol, tho,zghlmtlated by a one-electron oxidant, most ;lkely 1s the result of an electrophlllc substitution of the azeplne ring, ~rvolvlng disproportlonatlon of the orlglnally formed phenoxy radical. The formatIon of -bd supports the azeplcone structure 1 and rules out the lsomerlc structure -11 whose prec;irsor10 ~0uId be formed by ConJugate addltlon Of methylamlre to splroqu~~,ol

4.

ether 1.

IJncb%rgedIZiqR spectra after 5 mln at 525'.

5.

Cf. L.A

6

Ila

Faquette, 5. Amer. Chem. Sot , 06,

:alcd

IF (Imr)

for : 29'45-ii2(439.S~)_,~, 3370

7 03 (6, ;= J=

9 2~1

& IR

ralcd (qBr)

J=

t? 5 Fz,

1 30

(Q,

(Droan),

2.5

‘),

d7,

2

6.~5

42

(5,

1),

3 56

(d,

1 26 (s,

c=

y

I),

H.n. Hoimqulst, Z. C;rg L'hem,,2, Prepared

9.

L A. ?aquette and ’ C. rar;ey, Nm 6.65 9),

11

d) b)

1L’

Cf

by

for

(d,

Ii v D G

,=

9);

i

72 -0,

Y

’

t (d,

24

J= (s,

;Tf= 9 lie,

,

9 IIz,

‘),

2+9/

(d,

31,

1.47

(b,

91,

kz,

I),

18). ;~57gy;y(d,

I),

;! 42

(s,

4’64

(1969)

': ~C1~-1)yr Ld~iifwt3iysZ) ox1aaLloi1of c'-t-b~tyi-4-trLtylp!~enult (495.‘>)

C 32h49:‘L3

(CDL1 3,

1.25

(s,

3 53

97y;;

-IL,

8.

Calcd

1.20

;k i~_O~y5H;z~O;~~

9)

7.

10

Y),

qoy~zj

, d ~~‘01)

for C 1,?,,2~~:“:,;it3~~~~)(~~~~~~.~~~~~~

18),

(1964).

(s, I), 6.25 (-7 I),

1

3),

500

3, 70.52

12 F (CXl

?SnFl LO>

I),

13 (8,

'9.2C,

11

3 wm) 2 5 ru,

(s,

9),

XELrpV?, Bewltt,

y J

25

l),

1.20 i

i C,

(T,

6.25 (s,

9),

‘uc_&ov ‘Fiern

L.A. Faquette in J F

Amer. I.2em sot , 3; T-.53,

1 ?I), (d,

(s, II i

296

Ryder,

1969 F'rt,;,dew York ;r,dLoi,ai,-

j 2: 2.5

J=

0.93 ard

;o~.,

H. 9

96

(d,

Fz,

I),

bour.d-

J=

3595 C,

(1967).

77.26;

Ii,

9.76.

2.5

Ez,

I),

6.98

(d,

J=

3 88

(m,

4)~

2.70

(m,

4),

2.5 1.38

(s.

9) rnl?Pkrl,

Zhur.org.Khm.,

4,

1594

(1968)

(1911)

""orberre",o,d Aromatics", Vol.I, p. 249, Academic -