Silanes containing phenothiazine-S-oxide or phenothiazine-S,S-dioxide groups and the use thereof in OLEDs

1. A compound of the general formula I

in which

X is SO 2 or SO;

R 1 is in each case independently optionally substituted aryl, optionally substituted heteroaryl or optionally substituted alkyl;

R 2 , R 3 are in each case independently optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl or substituents having donor or acceptor action;

m is 1, 2, 3 or 4;

n is 1 or 2;

o, p are each independently 0, 1, 2, 3 or 4;

L is a bridging group selected from the group consisting of

—CH 2 —(B) j — and optionally substituted heteroarylene;

R 4 , R 5 , R 6 are in each case independently optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl or substituents having donor or acceptor action;

q, r, s are each independently 0, 1, 2, 3 or 4;

B is an alkylene bridge —C k H 2k —CH 2 —, in which one or more nonadjacent CH 2 groups of the —C k H 2k — unit may be replaced by oxygen or NR 7 ;

R 7 is hydrogen or alkyl;

k is 1, 2, 3, 4, 5, 6, 7 or 8; and

j is 0 or 1.

2. The compound according to claim 1 , in which:

X is SO 2 ;

m is 2, 3 or 4;

o, p are each 0, 1 or 2;

L is

 and

q is 0, 1 or 2.

3. The compound according to claim 1 , wherein at least two of the L or R 1 radicals or groups bonded to the Si are aromatic radicals or groups.

4. The compound according to claim 1 , in which:

L is

 and

o, p

and q are each 0.

5. An OLED comprising at least one compound according to claim 1 .

6. An OLED wherein at least one compound according to claim 1 is used as a matrix material and/or a blocker material.

7. The OLED according to claim 6 , wherein the matrix material and/or blocker material is used together with a triplet emitter.

8. A light-emitting layer comprising at least one compound according to claim 1 and at least one triplet emitter.

9. A hole and/or exciton blocker layer comprising at least one compound according to claim 1 .

10. A process for preparing compounds according to claim 1 , comprising:

(i) preparing a phenothiazine derivate (II)

in which

R 2 , R 3 are in each case independently optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl or a radical having donor or acceptor action;

o, p are each independently 0, 1, 2, 3 or 4;

L is a bridging group selected from the group consisting of

—CH 2 —(B) j — and optionally substituted heteroarylene;

R 4 , R 5 , R 6 are in each case independently optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl or substituents having donor or acceptor action;

q, r, s are each independently 0, 1, 2, 3 or 4;

B is an alkylene bridge —C k H 2k —CH 2 —, in which one or more nonadjacent CH 2 groups of the —C k H 2k — unit may be replaced by oxygen or NR 7 ;

R 7 is hydrogen or alkyl;

k is 1, 2, 3, 4, 5, 6, 7 or 8;

j is 0 or 1; and

Y is a halogen selected from the group consisting of F, Cl and Br;

by reacting phenothiazine or a phenothiazine derivate of the formula (III)

in which R 2 , R 3 , o and p are each as defined above

with a bifunctional compound of the formula (IV)

Z-L-Y  (IV)

in which L and Y are each as defined above and

Z is iodine, fluorine, bromine or tosyl;

(ii) preparing phenothiazine derivates of the formula (V)

in which the radicals and indices are each as defined above, and

m is 1, 2, 3 or 4, and

n is 1 or 2,

by reacting the phenothiazine derivate (II) with a haloalkyl/arylsilane of the general formula (VIa) or with an alkoxysilane of the general formula (VIb)

(R 8 ) t Si(Hal) 4-t   (VIa)

(R 8 ) t Si(OR 9 ) 4-t   (VIb)

in which

R 8 is optionally substituted aryl, optionally substituted heteroaryl or optionally substituted alkyl;

Hal is a halogen;

t is 1, 2 or 3; and

R 9 is alkyl, and

(iii) preparing the phenothiazine S-oxide or S,S-dioxide derivatives of the formula (I)

by reacting the phenothiazine derivates of the formula (V) with an oxidizing agent.

11. The method of using compounds according to claim 1 in OLEDs.

12. Stationary visual display units of computers, televisions, printers, kitchen appliances, advertising panels, illuminations, and information panels and mobile visual display units in cellphones, laptops, digital cameras, and vehicles and destination displays on buses and trains and illumination units, comprising at least one organic light-emitting diode according to claim 5 .