Organic semiconductors

1. An oligomer or polymer comprising one or more divalent units of formula I

wherein R is, on each occurrence identically or differently, straight-chain or branched alkyl having 1 to 20 C atoms,

and X is on each occurrence identically or differently is Si or Ge.

2. The polymer according to claim 1 , according to formula IV:

* (A) x -(B) y n *  IV

wherein

A is a unit of formula I or Formula II

—[(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ]—  II

wherein

U is a unit of formula I,

Ar 1 , Ar 2 , Ar 3 are, on each occurrence identically or differently, and independently of each other, aryl or heteroaryl that is different from U, and is optionally substituted, by one or more groups R S ,

R S is on each occurrence identically or differently F, Br, Cl, —CN, —NC, —NCO, —NCS, —OCN, —SCN, —C(O)NR 0 R 00 , —C(O)X 0 , —C(O)R 0 , —NH 2 , —NR 0 R 00 , —SH, —SR 0 , —SO 3 H, —SO 2 R 0 , —OH, —NO 2 , —CF 3 , —SF 5 , optionally substituted silyl or hydrocarbyl with 1 to 40 C atoms that is optionally substituted and optionally comprises one or more hetero atoms, or P-Sp-,

R 0 and R 00 are independently of each other H or optionally substituted C 1-40 hydrocarbyl,

P is a polymerisable or crosslinkable group,

Sp is a spacer group or a single bond,

X 0 is halogen,

a, b, c are on each occurrence identically or differently 0, 1 or 2,

d is on each occurrence identically or differently 0 or an integer from 1 to 10,

B is a unit that is different from A and comprises one or more aryl or heteroaryl groups that are optionally substituted,

x is >0 and ≤1,

y is ≥0 and <1,

x+y is 1, and

n is an integer>1.

3. The polymer according to claim 1 , comprising a divalent unit that is selected from the following formulae

*—[(Ar 1 —U—Ar 2 ) x —(Ar 3 ) y ] n —*  IVa

*—[(Ar 1 —U—Ar 2 ) x —(Ar 3 —Ar 3 ) y ] n —*  IVb

*—[(Ar 1 —U—Ar 2 ) x —(Ar 3 —Ar 3 —Ar 3 ) y ] n —*  IVc

*—[(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ] n —*  IVd

*—([(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ] x —[(Ar 1 ) a —(A 1 ) b —(Ar 2 ) c —(Ar 3 ) d ] y ) n —*  IVe

wherein U, is a unit or formula I, and

Ar 1 , Ar 2 , Ar 3 are, on each occurance identically or differently, and independently of each other, aryl or heteroaryl that is different from U, is optionally substituted, by one or more groups R S ,

R 0 and R 00 are independently of each other H or optionally subsituted C 1−40 hydrocarbyl,

P is a polymerisable or crosslinkable group,

Sp is a spacer group or a single bond,

X 0 is halogen,

a, b, c are on each occurrence identically or differently 0, 1 or 2,

d is on each occurence identically or different 0 or an integer from 1 to 10,

A 1 is on each occurrence identically or differently, an aryl or heteroaryl group that is different from U and Ar 1-3 , has 5 to 30 ring atoms, is optionally substituted by one or more groups R S which is on each occurence identically or differently F, Br, Cl, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(O)NR 0 R 00 , -C(O)X 0 , -C(O)R 0 , -NH 2 , -NR 0 R 00 , SH, -SR 0 , -SO 3 H, -SO 2 R 0 , -OH, -NO 2 , -CF 3 , -SF 5 , optionally substituted silyl or hydrocarbyl with 1 to 40 C atoms that is optionally substituted and optionally comprises one or more hetero atoms, or P-Sp-, and is selected from aryl or heteroaryl groups having electron donor properties, and

x is >0 and ≤1,

y is ≥0 and <1,

x+y is 1, and

n is an integer >1, wherein these polymers can be alternating or random copolymers, and

wherein formula IVd and IVe in at least one of the repeating units [(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ] and in at least one of the repeating units [(Ar 1 ) a —(A 1 ) b —(Ar 2 ) c —(Ar 3 ) d ] b is at least 1.

4. An oligomer of formula VII

wherein,

R is, on each occurrence identically or differently, straight-chain or branched alkyl having 1 to 20 C atoms,

and X is on each occurrence identically or differently is Si or Ge

Z 1 denotes a single bond, (CY 1 =CY 2 ) h , (C≡C) h , wherein h=1 or 2, or Ar 5 ,

Y 1 and Y 2 are independently of each other H, F, Cl or CN and

Ar 5 is aryl or heteroaryl that is different from Formula I, has 5 to 30 ring atoms and is optionally substituted,

R 7 and R 8 independently of each other denote H, F, Br, Cl, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(O)NR 0 R 00 , -C(O)X 0 , -C(O)R 0 , -C(O)OR 0 , -O-C(O)R 0 , -NH 2 , -NR 0 R 00 , -SH, -SR 0 , -SH 3 H, -SO 2 R 0 , -OH, -NO 2 , -CF 3 , -SF 5 , P-Sp-, or optionally substituted silyl or hydrocarbyl with 1 to 40 C atoms that is optionally substituted and optionally comprises one or more hetero atoms, and wherein one or more C atoms are optionally replaced by a hetero atom, and

R and R 00 are independently of each other H or optionally substituted C 140 hydrocarbyl, and

X 0 is halogen, and g is 1, 2 or 3 ,

P is a polymerisable or crosslinkable group,

Sp is a spacer group or a single bond.

5. A polymer according to claim 1 , of formula V

R 5 -chain-R 6 V

wherein “chain” is a polymer chain selected from formulas IV, IVa-IVe and IV 1 -IV 5

* (A) x -(B) y n *  IV

*—[(Ar 1 —U—Ar 2 ) x —(Ar 3 ) y ] n —* IVa

*—[(Ar 1 —U—Ar 2 ) x —(Ar 3 —Ar 3 ) y ] n —* IVb

*—[(Ar 1 —U—Ar 2 ) x —(Ar 3 —Ar 3 —Ar 3 ) y ] n —* IVC

*—[(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ] n —* lVd

*—([(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ] x —[(Ar 1 ) a —(A 1 ) b —(Ar 2 ) c —(Ar 3 ) d ] y ) n —* IVe

A is a unit of Formula I or Formula II

I wherein R is, on each occurrence identically or differently, straight-chain or branched alkyl having 1 to 20 C atoms,

and X is on each occurrence identically or differently is Si or Ge —[(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ]—II

U is a unit of formula I,

Ar 1 , Ar 2 , Ar 3 are, on each occurrence identically or differently, and independently of each other, aryl or heteroaryl that is different from U, is optionally substituted, by one or more groups R S ,

R S is on each occurrence identically or differently F, Br, Cl, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(O)NR 0 R 00 , -C(O)X 0 , -C(O)R 0 , -NH 2 , -NR 0 R 00 , -SH, -SR 0 , -SO 3 H, -SO 2 R 0 , -OH, -NO 2 , -CF 3 , -SF 5 , optionally substituted silyl or hydrocarbyl with 1 to 40 C atoms that is optionally substituted and optionally comprises one or more hetero atoms, or P-Sp-,

R 0 and R 00 are independently of each other H or optionally substituted C 1-40 hydrocarbyl,

P is a polymerisable or crosslinkable group,

Sp is a spacer group or a single bond,

X 0 is halogen,

a, b, c are on each occurrence identically or differently 0, 1 or 2,

d is on each occurrence identically or differently 0 or an integer from 1 to 10,

B is a unit that is different from A and comprises one or more aryl or heteroaryl groups that are optionally substituted,

x is >0 and ≤1,

y is ≥0 and <1,

x+y is 1, and

n is an integer >1

A 1 is on each occurrence identically or differently an aryl or heteroaryl group that is different from U and Ar 1-3 , has 5 to 30 ring atoms, is optionally substituted by one or more groups R S and is selected from aryl or heteroaryl groups having electron donor properties,

wherein in formula IVd and IVe in at least one of the repeating units [(Ar 1 ) a —(U) b —(Ar 2 ) c —(Ar 3 ) d ] and in at least one of the repeating units [(Ar 1 ) a —(A 1 ) b —(Ar 2 ) c —(Ar 3 ) d ] b is at least 1,

R is, on each occurrence identically or differently, straight-chain or branched alkyl having 1 to 20 C atoms and

R′ is on each occurrence identically or differently F, Br, Cl, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(O)NR 0 R 00 , -C(O)X 0 , -C(O)R 0 , -NH 2 , -NR 0 R 00 , -SH, -SR 0 , -SO 3 H, -SO 2 R 0 , -OH, -NO 2 , -CF 3 , -SF 5 , optionally substituted silyl or hydrocarbyl with 1 to 40 C atoms that is optionally substituted and optionally comprises one or more hetero atoms, or P-Sp-

and R 5 and R 6 denote independently of each other F, Br, Cl, H, -CH 2 Cl, -CHO, -CH=CH 2 , -SiR′R″R″′, -SnR′R″R″′, -BR′R″, -B(OR′)(OR″), -B(OH) 2 , -ZnCl, -MgCl, -MgBr or P-Sp-, R′, R″ and R′″ have independently of each other one of the meanings of R 0 , and two of R′, R″ and R″′ may also form a ring together with the hetero atom to which they are attached.

6. The polymer according to claim 5 , wherein one or more of Ar 1 , Ar 2 and Ar 3 denote aryl or heteroaryl selected from the group consisting of the following formulae

wherein R 11 , R 12 , R 13 ,R 14 , R 15 , R 16 , R 17 and R 18 independently of each other denote H or on each occurrence identically or differently F, Br, Cl, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(O)NR 0 R 00 , -C(O)X 0 , -C(O)R 0 , -NH 2 , -NR 0 R 00 , -SH, -SR 0 , -SO 3 H, -SO 2 R 0 , -OH, -NO 2 , -CF 3 , -SF 5 , optionally substituted silyl or hydrocarbyl with 1 to 40 C atoms that is optionally substituted and optionally comprises one or more hetero atoms, or P-Sp-,

R 0 and R 00 are independently of each other H or optionally substituted C 1-40 hydrocarbyl,

P is a polymerisable or crosslinkable group,

Sp is a spacer group or a single bond,

X 0 is halogen.

7. The polymer according to claim 5 , wherein one or more of the units Ar 3 and A 1 denote aryl or heteroaryl selected from the group consisting of the following formulae

wherein R 11 , R 12 , R 13 , R 14 , R 15 and R 16 independently of each other denote H or on each occurrence identically or differently F, Br, Cl, -CN, -NC, -NCO, -NCS, -OCN, -SCN, -C(O)NR 0 R 00 , -C(O)X 0 , -C(O)R 0 , -NH 2 , -NR 0 R 00 , -SH, -SR 0 , -SO 3 H, -SO 2 R 0 , -OH, -NO 2 , -CF 3 , -SF 5 , optionally substituted silyl or hydrocarbyl with 1 to 40 C atoms that is optionally substituted and optionally comprises one or more hetero atoms, or P-Sp-,

R 0 and R 00 are independently of each other H or optionally substituted C 1-40 hydrocarbyl,

P is a polymerisable or crosslinkable group,

Sp is a spacer group or a single bond,

X 0 is halogen.