# Electronic Supplementary Material (ESI) for RSC Advances.
# This journal is © The Royal Society of Chemistry 2016

####################################################################### 
# 
# This file contains crystal structure data downloaded from the 
# Cambridge Structural Database (CSD) hosted by the Cambridge 
# Crystallographic Data Centre (CCDC).
# 
# Full information about CCDC data access policies and citation 
# guidelines are available at http://www.ccdc.cam.ac.uk/access/V1 
# 
# Audit and citation data items may have been added by the CCDC. 
# Please retain this information to preserve the provenance of 
# this file and to allow appropriate attribution of the data. 
# 
#######################################################################

data_anhydride
_database_code_depnum_ccdc_archive 'CCDC 1498507'
_audit_update_record             
;
2016-08-10 deposited with the CCDC.
2016-10-31 downloaded from the CCDC.
;

_audit_creation_method           SHELXL-97
_chemical_name_systematic        
4,4,4',4'-tetramethyl-3,3',4,4'-tetrahydro-2,2'-spirobi[furo[3,4-g]chromene]-6,6',8,8'-tetraone
_chemical_name_common            'siprobichroman dianhydride'
_chemical_formula_moiety         'C25 H20 O8'
_chemical_formula_sum            'C25 H20 O8'
_chemical_melting_point          ?

_exptl_crystal_description       parallelepiped
_exptl_crystal_colour            grey

_diffrn_ambient_temperature      150(2)
_chemical_formula_weight         448.41

loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_H-M   'C 2/c'
_symmetry_int_tables_number      15
_chemical_absolute_configuration ?

loop_
_symmetry_equiv_pos_as_xyz
'x, y, z'
'-x, y, -z+1/2'
'x+1/2, y+1/2, z'
'-x+1/2, y+1/2, -z+1/2'
'-x, -y, -z'
'x, -y, z-1/2'
'-x+1/2, -y+1/2, -z'
'x+1/2, -y+1/2, z-1/2'

_cell_length_a                   26.146(2)
_cell_length_b                   10.3960(5)
_cell_length_c                   20.1104(16)
_cell_angle_alpha                90.00
_cell_angle_beta                 127.778(12)
_cell_angle_gamma                90.00
_cell_volume                     4320.5(5)
_cell_formula_units_Z            8
_cell_measurement_temperature    150(2)
_cell_measurement_reflns_used    2536
_cell_measurement_theta_min      3.1190
_cell_measurement_theta_max      28.8480
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.23
_exptl_crystal_density_meas      ?
_exptl_crystal_density_diffrn    1.379
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             1872
_exptl_absorpt_coefficient_mu    0.104
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_correction_T_min  0.99525
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_process_details   
; 
CrysAlisPro, Agilent Technologies, 
Version 1.171.37.31 (release 14-01-2014 CrysAlis171 .NET) 
(compiled Jan 14 2014,18:38:05) 
Empirical absorption correction using spherical harmonics, 
 implemented in SCALE3 ABSPACK scaling algorithm. 
;

_exptl_special_details           
; 
 ? 
;
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_source                   'fine-focus sealed tube'
_diffrn_radiation_monochromator  graphite
_diffrn_measurement_device_type  'CCD detector'
_diffrn_measurement_method       'ω scans'
_diffrn_detector_area_resol_mean ?
_diffrn_reflns_number            9874
_diffrn_reflns_av_R_equivalents  0.0298
_diffrn_reflns_av_sigmaI/netI    0.0588
_diffrn_reflns_limit_h_min       -33
_diffrn_reflns_limit_h_max       29
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_limit_l_max       25
_diffrn_reflns_theta_min         2.83
_diffrn_reflns_theta_max         29.30
_reflns_number_total             4978
_reflns_number_gt                3434
_reflns_threshold_expression     >2sigma(I)

_computing_data_collection       
; 
CrysAlis CCD, Oxford Diffraction Ltd., 
Version 1.171.32.29 (release 10-06-2008 CrysAlis171 .NET) 
(compiled Jun 10 2008,16:49:55) 
;
_computing_cell_refinement       
; 
CrysAlis RED, Oxford Diffraction Ltd., 
Version 1.171.32.29 (release 10-06-2008 CrysAlis171 .NET) 
(compiled Jun 10 2008,16:49:55) 
;
_computing_data_reduction        
; 
CrysAlis RED, Oxford Diffraction Ltd., 
Version 1.171.32.29 (release 10-06-2008 CrysAlis171 .NET) 
(compiled Jun 10 2008,16:49:55) 
;
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'

_refine_special_details          
; 
 Refinement of F² against ALL reflections.  The weighted R-factor wR and 
 goodness of fit S are based on F², conventional R-factors R are based 
 on F, with F set to zero for negative F². The threshold expression of 
 F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is 
 not relevant to the choice of reflections for refinement.  R-factors based 
 on F² are statistically about twice as large as those based on F, and R- 
 factors based on ALL data will be even larger. 
;

_refine_ls_structure_factor_coef Fsqd
_refine_ls_matrix_type           full
_refine_ls_weighting_scheme      calc
_refine_ls_weighting_details     
'calc w=1/[σ²(Fo²)+(0.0421P)²+1.6104P] where P=(Fo²+2Fc²)/3'
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_atom_sites_solution_hydrogens   geom
_refine_ls_hydrogen_treatment    constr
_refine_ls_extinction_method     none
_refine_ls_extinction_coef       ?
_refine_ls_number_reflns         4978
_refine_ls_number_parameters     298
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0883
_refine_ls_R_factor_gt           0.0529
_refine_ls_wR_factor_ref         0.1176
_refine_ls_wR_factor_gt          0.1014
_refine_ls_goodness_of_fit_ref   1.024
_refine_ls_restrained_S_all      1.024
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000

loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_occupancy
_atom_site_symmetry_multiplicity
_atom_site_calc_flag
_atom_site_refinement_flags
_atom_site_disorder_assembly
_atom_site_disorder_group
O1 O 0.20098(5) 0.13011(12) 0.02180(7) 0.0243(3) Uani 1 1 d . . .
O2 O 0.29347(8) -0.17249(17) -0.10269(10) 0.0501(4) Uani 1 1 d . . .
O3 O 0.35936(7) -0.27257(16) 0.02257(9) 0.0452(4) Uani 1 1 d . . .
O4 O 0.41281(9) -0.33165(18) 0.15843(11) 0.0612(5) Uani 1 1 d . . .
O5 O -0.15573(6) 0.06139(16) -0.29293(8) 0.0425(4) Uani 1 1 d . . .
O6 O -0.12210(6) -0.12336(15) -0.21720(8) 0.0379(4) Uani 1 1 d . . .
O7 O -0.06144(7) -0.27478(16) -0.11833(9) 0.0448(4) Uani 1 1 d . . .
O8 O 0.13741(5) 0.06824(12) 0.06026(7) 0.0242(3) Uani 1 1 d . . .
C1 C 0.24548(8) 0.03327(18) 0.05056(10) 0.0214(4) Uani 1 1 d . . .
C2 C 0.24982(8) -0.01752(19) -0.01019(11) 0.0254(4) Uani 1 1 d . . .
H2A H 0.2229 0.0127 -0.0666 0.030 Uiso 1 1 calc R . .
C3 C 0.29453(9) -0.11268(19) 0.01519(11) 0.0276(4) Uani 1 1 d . . .
C4 C 0.31190(10) -0.1831(2) -0.03247(14) 0.0358(5) Uani 1 1 d . . .
C5 C 0.37380(11) -0.2629(2) 0.10274(15) 0.0424(5) Uani 1 1 d . . .
C6 C 0.33263(9) -0.1597(2) 0.09655(12) 0.0298(5) Uani 1 1 d . . .
C7 C 0.32848(9) -0.10889(19) 0.15667(11) 0.0281(4) Uani 1 1 d . . .
H7A H 0.3551 -0.1412 0.2126 0.034 Uiso 1 1 calc R . .
C8 C 0.28470(8) -0.00974(18) 0.13425(10) 0.0220(4) Uani 1 1 d . . .
C9 C 0.28038(8) 0.04928(18) 0.19989(10) 0.0226(4) Uani 1 1 d . . .
C10 C 0.23783(8) 0.17020(18) 0.16376(10) 0.0235(4) Uani 1 1 d . . .
H10A H 0.2212 0.1867 0.1959 0.028 Uiso 1 1 calc R . .
H10B H 0.2654 0.2442 0.1733 0.028 Uiso 1 1 calc R . .
C11 C 0.18094(8) 0.16572(18) 0.07138(10) 0.0216(4) Uani 1 1 d . . .
C12 C 0.14696(8) 0.29371(18) 0.03873(11) 0.0249(4) Uani 1 1 d . . .
H12A H 0.1776 0.3566 0.0437 0.030 Uiso 1 1 calc R . .
H12B H 0.1361 0.3237 0.0755 0.030 Uiso 1 1 calc R . .
C13 C 0.08476(8) 0.29456(19) -0.05278(11) 0.0258(4) Uani 1 1 d . . .
C14 C 0.04827(8) 0.16899(19) -0.07111(10) 0.0234(4) Uani 1 1 d . . .
C15 C -0.01487(9) 0.1550(2) -0.14518(11) 0.0283(4) Uani 1 1 d . . .
H15A H -0.0354 0.2238 -0.1843 0.034 Uiso 1 1 calc R . .
C16 C -0.04697(8) 0.0413(2) -0.16101(11) 0.0275(4) Uani 1 1 d . . .
C17 C -0.11330(9) 0.0031(2) -0.23219(12) 0.0333(5) Uani 1 1 d . . .
C18 C -0.06511(9) -0.1678(2) -0.14194(12) 0.0326(5) Uani 1 1 d . . .
C19 C -0.01825(8) -0.06090(19) -0.10565(11) 0.0252(4) Uani 1 1 d . . .
C20 C 0.04397(8) -0.05182(18) -0.03156(10) 0.0236(4) Uani 1 1 d . . .
H20A H 0.0638 -0.1217 0.0068 0.028 Uiso 1 1 calc R . .
C21 C 0.07654(8) 0.06398(18) -0.01535(10) 0.0213(4) Uani 1 1 d . . .
C22 C 0.34813(9) 0.0914(2) 0.27730(11) 0.0332(5) Uani 1 1 d . . .
H22A H 0.3767 0.0163 0.3021 0.050 Uiso 1 1 calc R . .
H22B H 0.3449 0.1305 0.3189 0.050 Uiso 1 1 calc R . .
H22C H 0.3659 0.1543 0.2601 0.050 Uiso 1 1 calc R . .
C23 C 0.25409(9) -0.0512(2) 0.22780(11) 0.0302(5) Uani 1 1 d . . .
H23A H 0.2108 -0.0784 0.1792 0.045 Uiso 1 1 calc R . .
H23B H 0.2516 -0.0135 0.2704 0.045 Uiso 1 1 calc R . .
H23C H 0.2831 -0.1258 0.2517 0.045 Uiso 1 1 calc R . .
C24 C 0.09908(9) 0.3091(2) -0.11637(11) 0.0334(5) Uani 1 1 d . . .
H24A H 0.1252 0.2361 -0.1107 0.050 Uiso 1 1 calc R . .
H24B H 0.1228 0.3893 -0.1051 0.050 Uiso 1 1 calc R . .
H24C H 0.0582 0.3110 -0.1737 0.050 Uiso 1 1 calc R . .
C25 C 0.04367(9) 0.4096(2) -0.06244(13) 0.0383(5) Uani 1 1 d . . .
H25A H 0.0345 0.4014 -0.0221 0.057 Uiso 1 1 calc R . .
H25B H 0.0029 0.4111 -0.1198 0.057 Uiso 1 1 calc R . .
H25C H 0.0674 0.4896 -0.0516 0.057 Uiso 1 1 calc R . .


_geom_special_details            
; 
 All esds (except the esd in the dihedral angle between two l.s. planes) 
 are estimated using the full covariance matrix.  The cell esds are taken 
 into account individually in the estimation of esds in distances, angles 
 and torsion angles; correlations between esds in cell parameters are only 
 used when they are defined by crystal symmetry.  An approximate (isotropic) 
 treatment of cell esds is used for estimating esds involving l.s. planes. 
;

loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_2
_geom_bond_publ_flag
O1 C1 1.370(2) . ?
O1 C11 1.4303(19) . ?
O2 C4 1.185(2) . ?
O3 C4 1.396(3) . ?
O3 C5 1.416(3) . ?
O4 C5 1.186(3) . ?
O5 C17 1.196(2) . ?
O6 C18 1.400(2) . ?
O6 C17 1.399(3) . ?
O7 C18 1.190(3) . ?
O8 C21 1.3719(19) . ?
O8 C11 1.435(2) . ?
C1 C8 1.404(2) . ?
C1 C2 1.398(2) . ?
C2 C3 1.369(3) . ?
C2 H2A 0.9500 . ?
C3 C6 1.383(3) . ?
C3 C4 1.481(3) . ?
C5 C6 1.470(3) . ?
C6 C7 1.383(2) . ?
C7 C8 1.394(3) . ?
C7 H7A 0.9500 . ?
C8 C9 1.521(2) . ?
C9 C23 1.533(2) . ?
C9 C10 1.535(3) . ?
C9 C22 1.541(2) . ?
C10 C11 1.510(2) . ?
C10 H10A 0.9900 . ?
C10 H10B 0.9900 . ?
C11 C12 1.509(2) . ?
C12 C13 1.538(2) . ?
C12 H12A 0.9900 . ?
C12 H12B 0.9900 . ?
C13 C14 1.523(3) . ?
C13 C25 1.538(3) . ?
C13 C24 1.544(2) . ?
C14 C21 1.407(3) . ?
C14 C15 1.397(2) . ?
C15 C16 1.369(3) . ?
C15 H15A 0.9500 . ?
C16 C19 1.381(3) . ?
C16 C17 1.474(3) . ?
C18 C19 1.474(3) . ?
C19 C20 1.381(2) . ?
C20 C21 1.393(2) . ?
C20 H20A 0.9500 . ?
C22 H22A 0.9800 . ?
C22 H22B 0.9800 . ?
C22 H22C 0.9800 . ?
C23 H23A 0.9800 . ?
C23 H23B 0.9800 . ?
C23 H23C 0.9800 . ?
C24 H24A 0.9800 . ?
C24 H24B 0.9800 . ?
C24 H24C 0.9800 . ?
C25 H25A 0.9800 . ?
C25 H25B 0.9800 . ?
C25 H25C 0.9800 . ?

loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_3
_geom_angle_publ_flag
C1 O1 C11 118.36(13) . . ?
C4 O3 C5 110.06(16) . . ?
C18 O6 C17 109.65(15) . . ?
C21 O8 C11 117.78(13) . . ?
O1 C1 C8 123.22(15) . . ?
O1 C1 C2 114.29(15) . . ?
C8 C1 C2 122.48(17) . . ?
C3 C2 C1 117.06(16) . . ?
C3 C2 H2A 121.5 . . ?
C1 C2 H2A 121.5 . . ?
C2 C3 C6 121.89(16) . . ?
C2 C3 C4 130.23(18) . . ?
C6 C3 C4 107.88(18) . . ?
O2 C4 O3 121.45(19) . . ?
O2 C4 C3 131.5(2) . . ?
O3 C4 C3 106.99(17) . . ?
O4 C5 O3 120.5(2) . . ?
O4 C5 C6 132.9(2) . . ?
O3 C5 C6 106.53(18) . . ?
C7 C6 C3 120.92(18) . . ?
C7 C6 C5 130.56(19) . . ?
C3 C6 C5 108.52(17) . . ?
C6 C7 C8 119.22(17) . . ?
C6 C7 H7A 120.4 . . ?
C8 C7 H7A 120.4 . . ?
C1 C8 C7 118.37(15) . . ?
C1 C8 C9 121.61(16) . . ?
C7 C8 C9 120.02(15) . . ?
C23 C9 C8 109.34(15) . . ?
C23 C9 C10 111.94(14) . . ?
C8 C9 C10 109.71(14) . . ?
C23 C9 C22 108.64(14) . . ?
C8 C9 C22 109.93(14) . . ?
C10 C9 C22 107.25(15) . . ?
C11 C10 C9 116.05(15) . . ?
C11 C10 H10A 108.3 . . ?
C9 C10 H10A 108.3 . . ?
C11 C10 H10B 108.3 . . ?
C9 C10 H10B 108.3 . . ?
H10A C10 H10B 107.4 . . ?
O1 C11 O8 107.62(13) . . ?
O1 C11 C12 107.12(14) . . ?
O8 C11 C12 110.82(14) . . ?
O1 C11 C10 111.12(13) . . ?
O8 C11 C10 107.62(13) . . ?
C12 C11 C10 112.45(15) . . ?
C11 C12 C13 115.79(15) . . ?
C11 C12 H12A 108.3 . . ?
C13 C12 H12A 108.3 . . ?
C11 C12 H12B 108.3 . . ?
C13 C12 H12B 108.3 . . ?
H12A C12 H12B 107.4 . . ?
C14 C13 C12 109.34(15) . . ?
C14 C13 C25 110.52(15) . . ?
C12 C13 C25 107.48(15) . . ?
C14 C13 C24 108.48(15) . . ?
C12 C13 C24 112.11(14) . . ?
C25 C13 C24 108.92(16) . . ?
C21 C14 C15 117.99(17) . . ?
C21 C14 C13 121.79(15) . . ?
C15 C14 C13 120.22(17) . . ?
C16 C15 C14 119.57(18) . . ?
C16 C15 H15A 120.2 . . ?
C14 C15 H15A 120.2 . . ?
C15 C16 C19 121.56(17) . . ?
C15 C16 C17 130.32(19) . . ?
C19 C16 C17 108.11(18) . . ?
O5 C17 O6 121.61(18) . . ?
O5 C17 C16 131.2(2) . . ?
O6 C17 C16 107.14(18) . . ?
O7 C18 O6 120.78(18) . . ?
O7 C18 C19 131.9(2) . . ?
O6 C18 C19 107.33(18) . . ?
C16 C19 C20 121.11(18) . . ?
C16 C19 C18 107.72(17) . . ?
C20 C19 C18 131.17(19) . . ?
C19 C20 C21 117.31(17) . . ?
C19 C20 H20A 121.3 . . ?
C21 C20 H20A 121.3 . . ?
O8 C21 C14 123.00(16) . . ?
O8 C21 C20 114.52(15) . . ?
C14 C21 C20 122.45(16) . . ?
C9 C22 H22A 109.5 . . ?
C9 C22 H22B 109.5 . . ?
H22A C22 H22B 109.5 . . ?
C9 C22 H22C 109.5 . . ?
H22A C22 H22C 109.5 . . ?
H22B C22 H22C 109.5 . . ?
C9 C23 H23A 109.5 . . ?
C9 C23 H23B 109.5 . . ?
H23A C23 H23B 109.5 . . ?
C9 C23 H23C 109.5 . . ?
H23A C23 H23C 109.5 . . ?
H23B C23 H23C 109.5 . . ?
C13 C24 H24A 109.5 . . ?
C13 C24 H24B 109.5 . . ?
H24A C24 H24B 109.5 . . ?
C13 C24 H24C 109.5 . . ?
H24A C24 H24C 109.5 . . ?
H24B C24 H24C 109.5 . . ?
C13 C25 H25A 109.5 . . ?
C13 C25 H25B 109.5 . . ?
H25A C25 H25B 109.5 . . ?
C13 C25 H25C 109.5 . . ?
H25A C25 H25C 109.5 . . ?
H25B C25 H25C 109.5 . . ?

_diffrn_measured_fraction_theta_max 0.843
_diffrn_reflns_theta_full        26.00
_diffrn_measured_fraction_theta_full 0.999
_refine_diff_density_max         0.263
_refine_diff_density_min         -0.219
_refine_diff_density_rms         0.047

