Substituted carboxyphthalocyanines (I), wherein both the tert-butyl and carboxyl groups located in the four isoindole rings are located independently in any of the four positions of the corresponding benzene ring of each isoindole ring, its regioisomers and mixtures thereof, can be used in the manufacture of organic and hybrid solar cells or as a photoactive dyes for molecular photovoltaic devices.
CLAIMS 1. A substituted carboxyphthalocyanine of structural formula I, <img class="EMIRef" id="457815-imgf000015-0001" /> I wherein both the tøt-butyl and carboxyl groups located in the four isoindole rings are located indiscriminately in any of the four positions of the corresponding benzene ring, its regioisomers and mixtures thereof. 2. Compound according to claim 1, wherein the carboxyl group located in the isoindole ring is located in any of positions 1 or 2 of the benzene ring. 3. Compound according to claim 1, wherein the tert-butyl groups located in the three isoindole rings are located indiscriminately in any of the two central positions of each one of the corresponding benzene rings of the isoindole rings of compound I. 4. Compound according to claim 1, selected from the group of regioisomers consisting of: 9, 16, 23-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); 9, 16, 24-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); 9, 17, 23-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); 9, 17, 24-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); 10, 16, 23-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); 10, 16, 24-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); 10, 17, 23-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); 10, 17, 24-tri-tert-butyl-2-carboxy-5,28:14,19-diimino-7,12:21,26-dinitrilo-tetrabenzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II); and mixtures thereof. 5. Compound according to claim 1, comprising a mixture of regioisomers 9(10), 16(17), 23(24)-tri-tert-butyl-2-carboxy-5,28:14,19-diirnino-7,12:21,26-dinitrilo-tetra- benzo[c, h, m, r][l, 6, 11, 16]tetraazacycloeicosinato-(2<">)-N<29>, N<30>, N<31>, N<32> zinc (II). 6. A process for obtaining a substituted carboxyphthalocyanine of structural formula I according to anyone of claims 1 to 5, which comprises reacting a substituted tri-tøt-butylphthalocyanine of structural formula II <img class="EMIRef" id="457815-imgf000017-0001" /> II wherein the tert-butyl groups located in the three isoindole rings are located indiscriminately in any of the four positions of the corresponding benzene ring, and R<1> represents a functional group or a carbon-containing substituent which is converted into a carboxylic group, said R<1> group being located indiscriminately in any of the four positions of the corresponding benzene ring, with an adequate oxidizing reagent, to yield the compound I. 7. The process of claim 6, wherein R<1> is hydroxyalkyl, alkylcarbonyl, aldehyde, alkenyl or alkynyl. 8. The process of claim 7, wherein the oxidation of a compound II, wherein R<1> represents an aldehyde group, is performed with sodium chlorite/sulfamic acid; or wherein the oxidation of a compound II, wherein R<1> represents a hydroxymethyl or methylcarbonyl group, is performed with potassium permanganate; or wherein the oxidation of a compound II, wherein R<1> represents a vinyl or ethynyl group, is performed with ozone in non-reductive conditions. 9. Use of a substituted carboxyphthalocyanine according to anyone of claims 1 to 5 in the manufacture of an organic or hybrid solar cell, both as a pure regioisomer or as a mixture of two or more of them. 10. The use according to claim 9, wherein said substituted carboxyphthalocyanine is mixed with a dye or with an organic material, electronically active or not, or covalently incorporated to the backbone of a polymer, oligomer or copolymer. 11. The use according to claim 10, wherein said dye or organic material, electronically active or not, is an organic conducting polymer, oligomer or copolymer. 12. Use according to claim 11, wherein said organic conducting polymer, oligomer or copolymer, is a polyphenylenevinylene (PPV) or a polytiophene. 13. Use of a substituted carboxyphthalocyanine according to anyone of claims 1 to 5, in the manufacture of a hybrid solar cell, wherein said substituted carboxyphthalocyanine is adsorbed in a nanocrystalline semiconductor. 14. Use of a substituted carboxyphthalocyanine according to anyone of claims 1 to 5, as photoactive dye in a molecular photovoltaic device, said device comprising a mesoporous semiconductor, a photoactive dye and an electrolyte, wherein said photoactive dye comprises a substituted carboxyphthalocyanine according to anyone of claims 1 to 5. 15. The use according to claim 14, wherein said molecular photovoltaic device is combined to one or more, equal or different, molecular photovoltaic device(s) to form a tandem molecular photovoltaic device. 16. Use of a substituted carboxyphthalocyanine according to anyone of claims 1 to 5, as photoactive dye for co-sensitizing, together with one or more additional dye(s), a mesoporous film. 17. An organic or hybrid solar cell comprising a substituted carboxyphthalocyanine according to anyone of claims 1 to 5, optionally mixed with a dye or with an organic material, electronically active or not, or covalently incorporated to the backbone of a polymer, oligomer or copolymer. 18. A hybrid solar cell comprising a substituted carboxyphthalocyanine according to anyone of claims 1 to 5, adsorbed in a nanocrystalline semiconductor. 19. A molecular photovoltaic device comprising a photoactive dye, wherein said photoactive dye comprises a substituted carboxyphthalocyanine according to anyone of claims 1 to 5. 20. A tandem device comprising a combination of two or more molecular photovoltaic devices according to claim 19. 21. A co-sensitized mesoporous film comprising a substituted carboxyphthalocyanine according to anyone of claims 1 to 5 together with one or more additional dye(s).