DE2366394C1 - 4H-Benzo [4,5] cyclohepta [1,2-b] thiophene-4-one and its preparation - Google Patents

Description

in which R ^{1 is} hydrogen or a halogen or lower alkoxy radical in the 6- or 7-position and R ^{2 is} lower alkyl.

2. Process for the preparation of the compounds according to claim 1, characterized in that one Compounds of the general formula III,

ffl

in which R ^{1 has} the meaning given in claim 1 and X is chlorine or bromine, with alkanols of the general formula IV,

R ² OH IV

in which R ^{2 has} the meaning given in claim 1, reacts and the compounds of the general formula II obtained,

OR ²

in which R ¹ , R ¹ and X have the meanings given, subjected to an HX elimination in a manner known per se.

The invention relates to compounds of the general formula I,

OR-

in which R ^{1 has} the meaning given and X stands for chlorine or bromine, with alkanols of the general formula IV,

R ² OH

in which R ^{2 has} the meaning given, reacts and the compounds of the general formula II obtained,

OR ²

in which R ', R ² and X have the meaning given, subjected to an HX elimination in a manner known per se.

The reaction is expediently carried out with heating, preferably under reflux temperature. The addition of Silver nitrate, e.g. B. about 1 mole based on 1 mole of the compound of general formula III, accelerates the reaction and allows implementation at a low temperature, e.g. B. at room temperature. During the implementation arise as a uniform reaction product compounds of the general formula II: The ether group is surprisingly introduced practically quantitatively in the ΙΟ-position of the tricycle.

The acid HX is split off under alkaline conditions, for example by treating the compounds of the general formula II with a solution of potassium hydroxide in one of the prevailing Conditions of inert organic solvents such as methanol.

The compounds of general formula I are valuable intermediates. They can be used for the preparation pharmacologically active compounds, e.g. B.

of 4-piperidylidene-4H-benzo [4,5] cyclohepta [l, 2-b]

thiophene-I0 (9H) -ones can be used.

example 1

10-methoxy4H-benzo [4,5] cyclohepta [1,2-b]
thiophen-4-one

a) 9-Bromo-9,10-dihydro-10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (compound of Formula II)

10

A suspension of 20 g of 9,10-dibromo-9,10-dihydro-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one in 400 cm ^{3 of} methanol is refluxed for 5 hours. 9-Bromo-9,10-dihydro-10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (melting point 103 to 106 ° C.) is obtained.

b) 10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one

To a solution of 17.5 g of 9-bromo-9,10-dihydro-10-methoxy ^ H-benzo ^^ lcycloheptatl ^ -blthiophen ^ -one in 400 cm ^{3 of} methanol, 9 g of potassium hydroxide are added and the solution under Refluxed. After cooling to 0 to 5 ° C., the precipitated crystals are filtered off and recrystallized from methanol. In this way the pure 10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one, which melts at 164 to 166 ° C., is obtained. The microanalysis agrees with the formula C ₁₄ H ₁₀ O ₂ S. The structure was determined with the aid of the NMR and MS spectra.

Example 2

Analogously to Example 1 and using the following compounds of the formula II

- 9-Bromo-6-chloro-9,10-dihydro-10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (melting point 134 to 136 ° C),

- 9-Bromo-7-chloro-9,10-dihydro-10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (melting point 135 to 137 ° C),

- 6,9-dibromo-9,10-dihydro-10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one,

- 9-Bromo-9,10-dihydro-7,10-dimethoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one,

- 9-Bromo-10-butoxy-9,10-dihydro-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (m.p. 90 to 9Γ C) and

- 9-Bromo-10-ethoxy-9,10-dihydro-4H-benzo [4,5] cycloheptaD, 2-b] thiophen-4-one

the following compounds of the formula I are obtained:

- 6-chloro-10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (m.p. 220 to 222 ° C),

- 7-chloro-10-methoxy-4H-benzo [4,5] cyclohepta [!, 2-b] thiophen-4-one (melting point 216 to 218 ° C),

- 6-Bromo-10-methoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one,

- 7,10-Dimethoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (melting point 83 to 85 ° C),

- 10-Butoxy-4H-benzo [4,5] cyc! Ohepta [1,2-b] thiophen-4-one (mp 83 to 85 ° C) and

- 10-Ethoxy-4H-benzo [4,5] cyclohepta [1,2-b] thiophen-4-one (m.p. 127-129 ° C).

- blank page -

Claims (1)

Patent claims: 1. 4H-Benzo [4,5] cydohepta [1,2-b] thiophen-4-ones
of the general formula I, OR2 in which R ^{1 is} hydrogen or a halogen or lower alkoxy radical in the 6- or 7-position and R ^{2 is} lower alkyl. If R ^{1 is} halogen, halogen is in particular chlorine or bromine, preferably chlorine. If R ^{1 represents} a lower alkoxy group, this can in particular contain 1 to 4 carbon atoms and preferably represents the methoxy group. The symbol R ² stands in particular for a lower ίο _/ alkyl group of 1 to 4 carbon atoms, preferably for methyl. According to the invention, the compounds of general formula I are obtained by adding compounds of general formula III,