Synlett 2008(8): 1205-1207  
DOI: 10.1055/s-2008-1072718
LETTER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Glycoporphyrins by Cross-Metathesis Reactions

Fernando de C. da Silvaa,b, Vitor F. Ferreirab, Maria C. B. V. de Souzab, Augusto C. Toméa, Maria G. P. M. S. Nevesa, Artur M. S. Silvaa, José A. S. Cavaleiro*a
a Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
Fax: +351(234)370084; e-Mail: jcavaleiro@ua.pt;
b Departamento de Química Orgânica, Instituto de Química, Universidade Federal Fluminense, 24020-141 Niterói, Rio de Janeiro, Brazil
Further Information

Publication History

Received 1 February 2008
Publication Date:
16 April 2008 (online)

Abstract

An easy synthetic approach to glycoporphyrins from zinc(II)-2-vinyl-5,10,15,20-tetraphenylporphyrin or zinc(II)-protoporphyrin-IX dimethyl ester and O-allyl carbohydrate acetonides by cross-metathesis is reported.

9

General Procedure for Glycoporphyrins (6 and 7)
A solution of the metalloporphyrin (0.04 mmol) and Grubbs catalyst 2 (25% mol, 0.01 mmol) in degassed dry CH2Cl2 (2 mL) was heated at reflux, under argon, and the allyl sugar 5, dissolved in CH2Cl2 (1 mL), was immediately added by a syringe to the mixture. The reflux was kept as mentioned in Table [1] . The solvent was evaporated and the residue was purified by flash chromatography using a gradient of toluene-EtOAc as the eluent. The products 6 and 7 were obtained as red solids after crystallization from PE.
Selected Data for 6a
Mp 171-172 °C. 1H NMR (300.13 MHz, CDCl3): δ = 1.30 (s, 3 H, CH3), 1.47 (s, 3 H, CH3), 3.27 (s, 3 H, OCH3), 3.27 (dd, J = 8.3 and 9.7 Hz, 1 H, H-5′a), 3.47 (dd, J = 6.3 and 9.7 Hz, 1 H, H-5′b), 3.87 (dd, J = 2.1 and 5.9 Hz, 2 H, CH 2CH=CH), 4.22 (dd, J = 6.3 and 8.3 Hz, 1 H, H-4′), 4.52 (d, J = 5.9 Hz, 1 H, H-2′), 4.59 (d, J = 5.9 Hz, 1 H, H-3′), 4.86 (s, 1 H, H-1′), 6.20 (d, J = 15.6 Hz, 1 H, Hb), 6.30 (dt, J = 5.9 and 15.6 Hz, 1 H, Ha), 7.66-7.79 (m, 12 H, ArH), 8.05-8.22 (m, 8 H, Ar ortho), 8.81-8.94 (m, 6 H, H-7, H-8, H-12, H-13, H-17, H-18), 8.95 (d, J = 0.8 Hz, 1 H, H-3). 13C NMR (75.47 MHz, CDCl3): δ = 24.9 (CH3), 26.4 (CH3), 54.7 (OCH3), 70.4 (C-5), 72.2 (CH2CH=CH), 81.9 (C-3), 84.7 (C-2), 85.0 (C-4), 109.0 (C-1), 112.2 (C-6), 120.5, 121.0, 121.5, 126.5, 126.6, 126.7, 127.3, 127.4, 127.5, 127.8, 129.5 (C-a), 130.9, 131.5, 131.9, 132.0, 132.1, 132.2, 133.8 (C-b), 133.8, 133.9, 134.3, 142.7, 142.9, 146.7, 150.2, 150.3, 150.4, 150.7. UV/Vis (CHCl3): λmax (log ε) = 429 (4.57), 559 (4.28), 596.5 (3.63). HRMS (MALDI-TOF): m/z calcd for C56H46N4O5Zn [M]+: 918.2760; found: 918.2739.
Selected Data for 6b
Mp 165-166 °C. 1H NMR (300.13 MHz, CDCl3): δ = 1.32 (s, 3 H, CH3), 1.36 (s, 3 H, CH3), 1.48 (s, 3 H, CH3), 1.51 (s, 3 H, CH3), 3.60 (dd, J = 6.7 and 10.1 Hz, 1 H, H-6′a), 3.68 (dd, J = 6.7 and 10.1 Hz, 1 H, H-6′b), 3.93-4.05 (m, 1 H, H-5′), 3.93-4.05 (m, 2 H, CHR2 RCH=CH), 4.31 (dd, J = 1.9 and 8.0 Hz, 1 H, H-4′), 4.32 (dd, J = 2.5 and 5.0 Hz, 1 H, H-2′), 4.62 (dd, J = 2.5 and 8.0 Hz, 1 H, H-3′), 5.56 (d, J = 5.0 Hz, 1 H, H-1′), 6.22 (d, J = 15.5 Hz, 1 H, Hb), 6.41 (dt, J = 6.3 and 15.5 Hz, 1 H, Ha), 7.68-7.81 (m, 12 H, ArH), 8.06-8.22 (m, 8 H, Ar ortho), 8.82-8.94 (m, 6 H, H-7, H-8, H-12, H-13, H-17, H-18), 8.96 (s, 1 H, H-3). 13C NMR (75.47 MHz, CDCl3): δ = 24.5 (CH3), 26.9 (CH3), 26.1 (CH3), 66.8 (C-5), 68.9 (C-6), 70.6 (C-2), 70.7 (C-3), 71.2 (C-4), 72.8 (CH2CH=CH), 96.4 (C-1), 108.5 (C-8), 109.2 (C-7), 120.9, 121.2, 121.5, 126.5, 126.9, 127.4, 127.5, 127.9, 129.5 (C-a), 129.7, 131.0, 131.5, 131.9, 132.0, 132.1, 132.3, 133.9 (C-b), 134.4, 142.8, 142.9, 142.7, 143.1, 146.7, 148.6, 150.0, 150.1, 150.2, 150.3, 150.5, 150.8. UV/Vis (CHCl3): λmax (log ε) = 429 (4.55), 558.5 (4.25), 599.5 (3.62). HRMS (MALDI-TOF): m/z calcd for C59H50N4O6Zn [M]+: 974.3022; found: 974.3006.
Selected Data for 6c Mp 190-191 °C. 1H NMR (300.13 MHz, CDCl3): δ = 1.32 (s, 3 H, CH3), 1.36 (s, 3 H, CH3), 1.38 (s, 3 H, CH3), 1.54 (s, 3 H, CH3), 4.06-4.11 (m, 1 H, H-6′a), 4.06-4.11 (m, 1 H, H-6′b), 4.06-4.11 (m, 2 H, CH 2CH=CH), 4.06-4.11 (m, 1 H, H-3′), 4.16 (dd, J = 2.9 and 7.6 Hz, 1 H, H-4′), 4.30-4.37 (m, 1 H, H-5′), 4.59 (d, J = 3.7 Hz, 1 H, H-2′), 5.93 (d, J = 3.7 Hz, 1 H, H-1′), 6.26 (d, J = 15.6 Hz, 1 H, Hb), 6.36 (dt, J = 5.9 and 15.6 Hz, 1 H, Ha), 7.69-7.80 (m, 12 H, ArH), 8.07-8.21 (m, 8 H, Ar ortho), 8.82-8.93 (m, 6 H, H-7, H-8, H-12, H-13, H-17, H-18), 8.94 (s, 1 H, H-3). 13C NMR (75.47 MHz, CDCl3): δ = 25.4 (CH3), 26.3 (CH3), 26.8 (CH3), 26.9 (CH3), 67.2 (C-6), 72.5 (C-5), 81.1 (C-4), 81.2 (C-3), 82.9 (C-2), 105.3 (C-1), 108.8 (C-8), 111.8 (C-7), 120.5, 121.1, 126.6, 126.8, 126.9, 127.1, 127.5, 127.6, 127.9, 129.7 (C-a), 130.1, 131.6, 131.9, 132.0, 132.1, 132.3, 133.9, 134.0 (C-b), 134.3, 134.4, 142.7, 142.9, 148.4, 150.1, 150.2, 150.3, 150.8. UV/Vis (CHCl3): λmax (log ε) = 429 (4.55), 558.5 (4.26), 595.5 (3.59). HRMS (MALDI-TOF): m/z calcd for C59H50N4O6Zn [M]+: 974.3022; found: 974.3014.
Selected Data for 7a
Mp 115-116 °C. 1H NMR (300.13 MHz, CDCl3): δ = 1.10 (s, 3 H, CH3), 1.17 (s, 3 H, CH3), 1.25 (s, 3 H, CH3), 1.31 (s, 3 H, CH3), 1.40 (s, 3 H, CH3), 1.41 (s, 3 H, CH3), 2.94-3.04 (m, 2 H, CH2), 3.37 (s, 3 H, CH3), 3.38 (s, 3 H, CH3), 3.44 (s, 3 H, CH3), 3.45 (s, 3 H, CH3), 3.61 (s, 3 H, OCH3), 3.61-3.89 (m, 4 H, H-5′), 3.62 (s, 3 H, OCH3), 3.64 (s, 3 H, OCH3), 3.74-3.90 (m, 2 H, CH2), 3.74-3.90 (m, 2 H, CH 2CH=CH), 3.99-4.14 (m, 4 H, CH2), 4.57 (d, J = 5.9 Hz, 1 H, H-2′) and 4.62 (d, J = 5.9 Hz, 1 H, H-2′), 4.67-4.73 (m, 2 H, H-4′), 4.91 (d, J = 5.9 Hz, 1 H, H-3′) and 4.93 (d, J = 5.9 Hz, 1 H, H-3′), 5.04 (s, 1 H, H-1′) and 5.06 (s, 1 H, H-1′), 6.12 (dt, J = 5.9 and 17.5 Hz, 1 H, Ha) and 6.11 (dt, J = 5.9 and 17.5 Hz, 1 H, Ha), 6.24 (d, J = 17.5 Hz, 1 H, Ha) and 6.23 (d, J = 17.5 Hz, 1 H, Ha), 9.30 (s, 1 H, H meso ), 9.26 (s, 1 H, H meso ), 9.17 (s, 1 H, H meso ), 9.11 (s, 1 H, H meso ). 13C NMR (75.47 MHz, CDCl3): δ = 11.4, 11.5, 12.4 and 12.5 (4 × CH3), 21.6 (CH2), 24.9 and 26.4 (CH3 of isopropylidene), 36.8 (CH2), 51.6 (CO2OCH3), 54.7 and 54.8 (OCH3), 71.1 (C-5′), 76.6 (CH2CH=CH), 77.4 (C-4′), 82.1 (C-5′), 85.0 and 85.1 (C-2′), 95.4, 96.5, 97.9 and 97.2 (CH in 5, 10, 15, 20 positions), 109.2 and 109.3 (C-1′), 112.3 (C-6′), 119.0 and 119.1, 129.2, 130.3 and 130.5, 135.3, 135.9, 136.0, 136.1, 136.4, 137.8, 138.0, 144.9, 145.6, 145.7, 145.9, 146.0, 146.1, 146.2, 146.4, 147.0, 147.1, 173.3 (C=O). UV/Vis (CHCl3): λmax (log ε) = 415.5 (5.36), 544 (4.20), 580.5 (4.28). HRMS (MALDI-TOF): m/z calcd for C56H68N4O14Zn [M]+: 1084.4023; found: 1084.4007.