Trifluoroethanol solvent facilitates selective N-7 methylation of purines.
Lebraud, Honorine; Cano, Celine; Carbain, Benoit; Hardcastle, Ian R.; Harrington, Ross W.; Griffin, Roger J.; Golding, Bernard T.; Organic & biomolecular chemistry 11 (2013) 1874–1878; doi:10.1039/c3ob27473j

data_7152836
_publ_section_title
;
 Trifluoroethanol solvent facilitates selective N-7 methylation of
 purines.
;
_journal_issue                   11
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1874
_journal_page_last               1878
_journal_paper_doi               10.1039/c3ob27473j
_journal_volume                  11
_journal_year                    2013
_chemical_formula_moiety         'C13 H17 I N4 O'
_chemical_formula_sum            'C13 H17 I N4 O'
_chemical_formula_weight         372.21
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.370(7)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   20.6041(14)
_cell_length_b                   10.2213(6)
_cell_length_c                   6.8832(5)
_cell_measurement_reflns_used    2746
_cell_measurement_temperature    150(2)
_cell_measurement_theta_max      28.5075
_cell_measurement_theta_min      2.8018
_cell_volume                     1449.58(17)
_computing_cell_refinement
;
CrysAlisPro, Agilent Technologies,
Version 1.171.34.49 (release 20-01-2011 CrysAlis171 .NET)
(compiled Jan 20 2011,15:58:25)
;
_computing_data_collection
;
CrysAlisPro, Agilent Technologies,
Version 1.171.34.49 (release 20-01-2011 CrysAlis171 .NET)
(compiled Jan 20 2011,15:58:25)
;
_computing_data_reduction
;
CrysAlisPro, Agilent Technologies,
Version 1.171.34.49 (release 20-01-2011 CrysAlis171 .NET)
(compiled Jan 20 2011,15:58:25)
;
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL and local programs'
_computing_structure_refinement  'Bruker SHELXTL'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      150(2)
_diffrn_detector_area_resol_mean 10.3968
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.974
_diffrn_measurement_device_type
'Oxford Diffraction Gemini A Ultra diffractometer'
_diffrn_measurement_method       'thick-slice \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'sealed tube with Enhance optics'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0000
_diffrn_reflns_av_sigmaI/netI    0.0325
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -7
_diffrn_reflns_number            2784
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.99
_diffrn_reflns_theta_min         2.81
_exptl_absorpt_coefficient_mu    2.208
_exptl_absorpt_correction_T_max  0.9572
_exptl_absorpt_correction_T_min  0.5572
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
'Thu Jun 14 11:59:21 2012'
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.705
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       lath
_exptl_crystal_F_000             736
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.02
_refine_diff_density_max         1.659
_refine_diff_density_min         -0.671
_refine_diff_density_rms         0.125
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.065
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     174
_refine_ls_number_reflns         2784
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.065
_refine_ls_R_factor_all          0.0500
_refine_ls_R_factor_gt           0.0428
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0470P)^2^+7.4793P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1069
_refine_ls_wR_factor_ref         0.1121
_reflns_number_gt                2450
_reflns_number_total             2784
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            c3ob27473j.txt
_cod_data_source_block           rjg120003_4f
_cod_database_code               7152836
_computing_special_details
;
TITL rjg120003 in P2(1)/c
CELL 0.71073 20.6041 10.2213 6.8832 90.000 90.370 90.000
ZERR 4.00 0.0014 0.0006 0.0005 0.000 0.007 0.000
LATT 1
SYMM -X, 0.5+Y, 0.5-Z
SFAC C H O I N
UNIT 52 68 4 4 16
TEMP -123
L.S. 8
BOND $H
CONF
REM colourless lath
SIZE 0.30 0.10 0.02
FMAP 2
PLAN 5
OMIT -3 52
ACTA 50
REM EXTI 0.000000
WGHT 0.047000 7.479300
BASF 0.08133
FVAR 3.09366
I 4 0.210392 1.123265 0.367526 11.00000 0.04477 0.01976 =
0.03526 0.00090 -0.00131 -0.00403
N1 5 0.211857 0.838883 0.405653 11.00000 0.01094 0.01650 =
0.01486 0.00138 0.00131 0.00020
C2 1 0.168732 0.934112 0.363538 11.00000 0.02193 0.01228 =
0.01172 0.00069 0.00289 0.00043
N3 5 0.107495 0.927642 0.321090 11.00000 0.02247 0.01759 =
0.01372 -0.00052 0.00076 0.00611
C4 1 0.085717 0.801703 0.317090 11.00000 0.01820 0.02238 =
0.01053 0.00132 0.00090 0.00432
C5 1 0.124899 0.694527 0.353320 11.00000 0.01431 0.01605 =
0.01028 0.00158 0.00241 -0.00006
C6 1 0.190181 0.716976 0.398228 11.00000 0.00906 0.01453 =
0.01208 -0.00100 0.00105 0.00242
N7 5 0.086332 0.585887 0.329083 11.00000 0.00854 0.01999 =
0.01551 -0.00262 -0.00077 -0.00168
C7 1 0.104307 0.449201 0.352293 11.00000 0.01629 0.01842 =
0.02702 -0.00264 0.00004 -0.00382
AFIX 137
H7A 2 0.068599 0.393471 0.306909 11.00000 -1.50000
H7B 2 0.113202 0.431107 0.489724 11.00000 -1.50000
H7C 2 0.143237 0.430892 0.275892 11.00000 -1.50000
AFIX 0
C8 1 0.027177 0.634250 0.279480 11.00000 0.01127 0.03822 =
0.01941 -0.00149 -0.00529 0.00010
AFIX 43
H8A 2 -0.009243 0.579774 0.253882 11.00000 -1.20000
AFIX 0
N9 5 0.024309 0.763373 0.269638 11.00000 0.01074 0.03253 =
0.01803 0.00200 -0.00163 0.00526
O10 3 0.229068 0.616617 0.434416 11.00000 0.00924 0.01205 =
0.03268 -0.00379 -0.00337 0.00099
C11 1 0.296781 0.641253 0.476166 11.00000 0.00791 0.02323 =
0.03476 -0.00994 -0.00749 0.00040
AFIX 23
H11A 2 0.307129 0.613305 0.610548 11.00000 -1.20000
H11B 2 0.305797 0.736110 0.465526 11.00000 -1.20000
AFIX 0
C12 1 0.338620 0.566768 0.334422 11.00000 0.00585 0.01677 =
0.02047 0.00405 0.00032 0.00008
AFIX 13
H12A 2 0.324917 0.591417 0.199679 11.00000 -1.20000
AFIX 0
C13 1 0.409445 0.607709 0.362788 11.00000 0.00970 0.02449 =
0.06047 -0.00790 0.00539 -0.00549
AFIX 23
H13A 2 0.413634 0.702693 0.337671 11.00000 -1.20000
H13B 2 0.422617 0.591297 0.499198 11.00000 -1.20000
AFIX 0
C14 1 0.454245 0.533491 0.228319 11.00000 0.01733 0.04466 =
0.05593 -0.00308 0.01231 0.00101
AFIX 23
H14A 2 0.444270 0.557312 0.091950 11.00000 -1.20000
H14B 2 0.499772 0.558645 0.256031 11.00000 -1.20000
AFIX 0
C15 1 0.446661 0.387340 0.253944 11.00000 0.02235 0.03608 =
0.04473 -0.01141 0.00805 0.00830
AFIX 23
H15A 2 0.461458 0.362355 0.385943 11.00000 -1.20000
H15B 2 0.474432 0.341445 0.158922 11.00000 -1.20000
AFIX 0
C16 1 0.376514 0.344341 0.225430 11.00000 0.03201 0.03161 =
0.04112 -0.01809 -0.00280 0.00859
AFIX 23
H16A 2 0.363591 0.357752 0.088090 11.00000 -1.20000
H16B 2 0.372665 0.249871 0.254916 11.00000 -1.20000
AFIX 0
C17 1 0.331457 0.420887 0.355808 11.00000 0.01641 0.01200 =
0.03434 -0.00098 0.00092 -0.00342
AFIX 23
H17A 2 0.286062 0.396200 0.325283 11.00000 -1.20000
H17B 2 0.340268 0.396515 0.492658 11.00000 -1.20000
HKLF 5
REM rjg120003 in P2(1)/c
REM R1 = 0.0428 for 2450 Fo > 4sig(Fo) and 0.0500 for all 2784 data
REM 174 parameters refined using 0 restraints
END
WGHT 0.0473 7.4449
REM Highest difference peak 1.659, deepest hole -0.671, 1-sigma level 0.125
Q1 1 0.2103 1.1284 0.1336 11.00000 0.05 1.66
Q2 1 0.2411 1.0578 0.3943 11.00000 0.05 0.88
Q3 1 0.1883 1.0404 0.3571 11.00000 0.05 0.83
Q4 1 0.1574 1.1813 0.3384 11.00000 0.05 0.73
Q5 1 0.0601 0.6152 0.3219 11.00000 0.05 0.55
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