A new benzazole synthesis

Tetrahedron Letters No.20, pp. 2365-2367.Pcrgamon Press Ltd. Printed in Great Britain.

A NEU BENZAZOLESYHTPISIS

LHideg Institute

of

and H.O.Bankovssky

Pharmacology,

Unirorsity

Hedioal

Sahool,

PBas, Bunguy (Beceired In .for

another

communication

the preparation

bonsimida%oles).

Oa heating

diamine

hydrazido,

the initial

benzasoles

in fair

In the present with

(1)

of bensasoles

c-phenylene

beneazoles

11 May 1965)

vith

ve described

recently

(benxthiasoles,

c-aminothiophenol,

an equivalent substances

vere

a nev method

bensoxazolos, c-aminophenol

amount of

isonicotinia

oonverted

into

or

P-(4*-pyridylj-

yields. letter,

the aid

of

ve report this

on the preparation

method.

vhero X = S, 0 or NE

2365

of ii-phenyl

NH

I:

59

16

(3) 102-103 102

(4) 290 (194.24)

'13"loN2

(195.22)

C13B9NP

(211.29)

c138gRS

(Mo1.wt.I'

Formula i!

N

x EtOHb) max.m~L(logt

242 13.071, 80.39 5.19 14.42 80.30 5.10 14.67 297 (3.15). 301 (3.16:

79.99 4.64 7.17 80.06 4.68 '7.23 298 (3.16)

---

296 (3.19)

73.90 4.29 6.63 ?3.?2i 4.59 6-50 24a (2.901, 290 (3.181,

C

Calcd.

I

b) Ultravioletspectra were recorded vith a Beckman 6-2400 model

a) All melting points were establishedin a Boetius melting apparatus

2aa-292

64

46

Yield

(2) 111-112 114

a) Found Ref. m.p. m.p* OC OC

I

2-Phony1Benxasoles

TABLF;1.

2367

13033

Equivalentamounts of the oomponentsuore heated 5 hours on metal bath (200')without any solvent.The oompletionof the reaction was indicatedby the end of formationof condensation products (water.hydrasine).The obtainedproducts were purified by rearystallization from aqueous ethanol.Wo ride reactiona were observed. The yields, melting pointa and ultravioletabsorption maxima of the threm phony1 benzaeolecompoundsare presentedin Table 1.

REFERENCES 1. K. Hideg and.B.0. Rankovstky,Acta Chim. Aoad. Sci. Hung. ~ In press. 2.

R.F. Hunter,J.

&9& _-__ 138.

3. S. Skraup, Liebins Ann. Chem. 522, 1 (1919). 4.

8. UeidenhaSen,Chem. Ber. $2, 2263 (1936).