Method for the preparation of a partially hydrogenated polyacene and an intermediate thereof

A method for the preparation of a partially hydrogenated polyacene comprising the step of:

• contacting a compound of formula (I):
• with a catalytically effective amount of a Au(I) catalyst,
• wherein each of R1, R2, R3 and R4, which may be the same or different, is independently selected from the group consisting of:
• hydrogen, halogen, straight chain or branched (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkyloxy, (C1-C6)thioalkyl, (C2-C6)alkylcarbonyl, (C2-C6)alkylcarbonyloxy, (C2-C6)alkyloxycarbonyl, a radical of formula Si((C1-C6)alkyl)3, (C2-C6)alkylcarbonylamino, (C2-C6)alkylaminocarbonyl, an aldehyde group, cyano, nitro, a radical of formula (II):
• with the condition that when one or more of R1, R2, R3 and R4 is a radical of formula (II) at least one carbon atom adjacent to the carbon atom bearing a radical of formula (II) is substituted with hydrogen;
• a (C6-C20)aryl optionally substituted at one or more positions with a radical selected from the group consisting of:
• halogen, (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkyloxy, (C1-C6)thioalkyl, (C2-C6)alkylcarbonyl, (C2-C6)alkylcarbonyloxy, (C2-C6)alkyloxycarbonyl, a radical of formula Si((C1-C6)alkyl)3, (C2-C6)alkylcarbonylamino, (C2-C6)alkylaminocarbonyl, cyano, nitro, an aldehyde group and a radical of formula (II) with the condition that at least one carbon atom adjacent to the carbon atom of the (C6-C20)aryl substituted with the radical of formula (II) is substituted with hydrogen;
• and a (C5-C20)heteroaryl optionally substituted at one or more positions with a radical selected from the group consisting of halogen, (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkyloxy, (C1-C6)thioalkyl, (C2-C6)alkylcarbonyl, (C2-C6)alkylcarbonyloxy, (C2-C6)alkyloxycarbonyl, a radical of formula Si((C1-C6)alkyl)3, (C2-C6)alkylcarbonylamino, (C2-C6)alkylaminocarbonyl, cyano, nitro, an aldehyde group and a radical of formula (II) with the condition that at least one carbon atom adjacent to the carbon atom of the (C5-C20)heteroaryl substituted with the radical of formula (II) is substituted with hydrogen;
• or, alternatively,
• one, two or three of the pairs R1 and R2, R2 and R3, and R3 and R4, together with the carbon atoms to which they are attached, form a ring system comprising 1 to 5 rings, each ring being isolated, fused or partially fused, and comprising from 5 to 6 members selected from the group consisting of:
• C, CH, CH2, CO, O, S, N and NR10, wherein R10 is selected from hydrogen and (C1-C6)alkyl, each ring being independently unsaturated, saturated or aromatic;
• and each ring being further optionally substituted with one or more radicals selected from the group consisting of:
• halogen, (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkyloxy, (C1-C6)thioalkyl, (C2-C6)alkylcarbonyl, (C2-C6)alkylcarbonyloxy, (C2-C6)alkyloxycarbonyl, a radical of formula Si((C1-C6)alkyl)3, (C2-C6)alkylcarbonylamino, (C2-C6)alkylaminocarbonyl, cyano, an aldehyde group and nitro and wherein when the ring system comprises at least one carbon-carbon double bond, the carbon atoms forming a double bond can further be substituted with a radical of formula (II) with the condition that the carbon atom forming the double bond adjacent to the carbon atom substituted with a radical of formula (II) is substituted with hydrogen;
• R7 is selected from the group consisting of hydrogen, (C1-C6)alkyl and (C1-C6)haloalkyl;
• R8 is selected from the group consisting of hydrogen, (C1-C6)alkyl, and (C1-C6)haloalkyl;
• R9 is a linear or branched (C1-C6)alkyl;
• and
• R11, R12, R13, R14 have the same meanings as R1, R2, R3, R4;
• R5 and R6 are each independently selected from the group consisting of:
• hydrogen, straight chain or branched (C1-C6)alkyl, (C1-C6)haloalkyl, a (C6-C20)aryl optionally substituted at one or more positions with a radical selected from the group consisting of halogen, (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkyloxy, (C1-C6)thioalkyl, (C2-C6)alkylcarbonyl, (C2-C6)alkylcarbonyloxy, (C2-C6)alkyloxycarbonyl, a radical of formula Si((C1-C6)alkyl)3, (C2-C6)alkylcarbonylamino, (C2-C6)alkylaminocarbonyl, cyano, nitro, an aldehyde group, and a radical of formula (II) with the condition that at least one carbon atom adjacent to the carbon atom of the (C6-C20)aryl substituted with the radical of formula (II) is substituted with hydrogen;
• and a (C5-C20)heteroaryl optionally substituted at one or more positions with a radical selected from the group consisting of:
• halogen, (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkyloxy, (C1-C6)thioalkyl, (C2-C6)alkylcarbonyl, (C2-C6)alkylcarbonyloxy, (C2-C6)alkyloxycarbonyl, a radical of formula Si((C1-C6)alkyl)3, (C2-C6)alkylcarbonylamino, (C2-C6)alkylaminocarbonyl, cyano, nitro, an aldehyde group, and a radical of formula (II) with the condition that at least one carbon atom adjacent to the carbon atom of the (C5-C20)heteroaryl substituted with the radical of formula (II) is substituted with hydrogen;
• or, alternatively,
• R5 and R6, together with the carbon atoms to which they are attached, form a ring system comprising 1 to 10 rings, each ring being isolated, fused or partially fused, and comprising from 5 to 6 members selected from the group consisting of C, CH, CH2, CO, O, S, N and NR10, wherein R10 is selected from hydrogen and (C1-C6)alkyl, each ring being independently unsaturated, saturated or aromatic, and each ring being further optionally substituted with one or more radicals independently selected from the group consisting of:
• halogen, (C1-C6)alkyl, (C1-C6)haloalkyl, (C1-C6)alkyloxy, (C1-C6)thioalkyl, (C2-C6)alkylcarbonyl, (C2-C6)alkylcarbonyloxy, (C2-C6)alkyloxycarbonyl, a radical of formula Si((C1-C6)alkyl)3, (C2-C6)alkylcarbonylamino, (C2-C6)alkylaminocarbonyl, cyano, an aldehyde group, and nitro,
• and wherein when the ring system comprises at least one carbon-carbon double bond, the carbon atoms forming a double bond can further be substituted with a radical of formula (II) with the condition that the carbon atom forming the double bond adjacent to the carbon atom substituted with a radical of formula (II) is substituted with hydrogen;
• to obtain a partially hydrogenated polyacene of formula (III):
• wherein the R15, R16, R17, R18, R19, R20 have the same meanings as R1, R2, R3, R4, R5, R6 respectively except when a radical of formula (II) is present in the compound of formula (I) then the diradical of formula (II′) is cyclized in a diradical of formula (IV) in the compound of formula (III)