Graphene nanoribbon precursors and monomers suitable for preparation thereof
Provided are graphene nanoribbon precursors comprising repeated units of the general formula (I) in which R 1 , R 2 are each H, halogen, —OH, —NH 2 , —CN, —NO 2 or a hydrocarbyl radical which has 1 to 40 carbon atoms and may be linear or branched, saturated or unsaturated and mono- or poly-substituted by halogen (F, Cl, Br, I), —OH, —NH 2 , —CN, and/or —NO 2 , where one or more CH 2 groups may also be replaced by —O—, —S—, —C(O)O—, —O—C(O)—, —C(O)—, —NH— or —NR—, in which R is an optionally substituted C 1 C 40 -hydrocarbyl radical, or an optionally substituted aryl, alkylaryl or alkoxyaryl radical.
1. A graphene nanoribbon precursor comprising repeat units of general formula (I)
in which
R 1 , R 2 are each H, halogen, —OH, —NH 2 , —CN, —NO 2 or a hydrocarbyl radical which has 1 to 40 carbon atoms and may be linear or branched, saturated or unsaturated and mono- or polysubstituted by halogen (F, Cl, Br, I), —OH, —NH 2 , —CN and/or —NO 2 , where one or more CH 2 groups may also be replaced by —O—, —S—, —C(O)O—, —O—C(O)—, —C(O)—, —NH— or —NR—, in which R is an optionally substituted C 1 -C 40 -hydrocarbyl radical, or an optionally substituted aryl, alkylaryl or alkoxyaryl radical.
2. A process for preparing graphene nanoribbon precursors, comprising the Yamamoto coupling reaction of monomers of the general formula (II)
in which
R 1 , R 2 are each H, halogen, —OH, —NH 2 , —CN, —NO 2 or a hydrocarbyl radical which has 1 to 40 carbon atoms and may be linear or branched, saturated or unsaturated and mono- or polysubstituted by halogen (F, Cl, Br, I), —OH, —NH 2 , —CN and/or —NO 2 , where one or more CH 2 groups may also be replaced by —O—, —S—, —C(O)O—, —O—C(O)—, —C(O)—, —NH— or —NR—, in which R is an optionally substituted C 1 -C 40 -hydrocarbyl radical, or an optionally substituted aryl, alkylaryl or alkoxyaryl radical, and
X is halogen, trifluoromethylsulfonate or diazonium.
3. A process for preparing monomers of the gene a formula (II), comprising the steps of
(i) reacting 1,3-di(biphenyl-3-yl)propan-7-one 7
with 4,4′-dihalobenzil 9
by Knoevenagel condensation to give the tetraarylcyclopentadienone 8
(ii) reacting the tetraarylcyclopentadienone 8 with a tolane 10
by Diels-Alder reaction to give the monomer of the general formula (II)
in which
R 2 are each H, halogen, —OH, —NH 2 , —CN, —NO 2 or a hydrocarbyl radical which has 1 to 40 carbon atoms and may be linear or branched, saturated or unsaturated and mono- or polysubstituted by halogen (F, Cl, Br, I), —OH, —NH 2 , —CN and/or —NO 2 , where one or more CH 2 groups may also be replaced by —O—, —S—, —C(O)O—, —O—C(O)—, —C(O)—, —NH— or —NR—, in which R is an optionally substituted C 1 -C 40 -hydrocarbyl radical, or an optionally substituted aryl, alkylaryl or alkoxyaryl radical, and
X is halogen, trifluoromethylsulfonate or diazonium.
4. A monomer for preparation of graphene nanoribbon precursors by Yamamoto coupling reaction, of the general formula (II)
in which
R 1 , R 2 are each H, halogen, —OH, —NH 2 , —CN, —NO 2 or a hydrocarbyl radical which has 1 to 40 carbon atoms and may be linear or branched, saturated or unsaturated and mono- or polysubstituted by halogen (F, Cl, Br, I), —OH, —NH 2 , —CN and/or where one or more CH 2 groups may also be replaced by —O—, —C(O)O—, —O—C(O)—, —C(O)—, —NH— or —NR—, in which R is an optionally substituted C 1 -C 40 -hydrocarbyl radical, or an optionally substituted aryl, alkylaryl or alkoxyaryl radical, and
X is halogen, trifluoromethylsulfonate or diazonium.