#------------------------------------------------------------------------------ #$Date: 2014-07-11 17:35:18 +0300 (Fri, 11 Jul 2014) $ #$Revision: 120071 $ #$URL: file:///home/coder/svn-repositories/cod/cif/1/50/46/1504695.cif $ #------------------------------------------------------------------------------ # # This file is available in the Crystallography Open Database (COD), # http://www.crystallography.net/ # # All data on this site have been placed in the public domain by the # contributors. # data_1504695 loop_ _publ_author_name 'Nakamura, Itaru' 'Sato, Takuma' 'Terada, Masahiro' 'Yamamoto, Yoshinori' _publ_section_title ; Chirality transfer in gold-catalyzed carbothiolation of o-alkynylphenyl 1-arylethyl sulfides. ; _journal_issue 13 _journal_name_full 'Organic letters' _journal_page_first 2649 _journal_page_last 2651 _journal_volume 10 _journal_year 2008 _chemical_absolute_configuration 'CHOOSE rm ad rmad syn or unk' _chemical_formula_moiety 'C31 H28 Br O3 S2 ' _chemical_formula_sum 'C31 H28 Br O3 S2' _chemical_formula_weight 592.58 _space_group_IT_number 4 _symmetry_cell_setting monoclinic _symmetry_Int_Tables_number 4 _symmetry_space_group_name_Hall 'P 2yb' _symmetry_space_group_name_H-M 'P 1 21 1' _cell_angle_alpha 90.0000 _cell_angle_beta 99.9391(17) _cell_angle_gamma 90.0000 _cell_formula_units_Z 2 _cell_length_a 14.010(4) _cell_length_b 6.504(2) _cell_length_c 14.749(5) _cell_measurement_reflns_used 4582 _cell_measurement_temperature 173.1 _cell_measurement_theta_max 27.5 _cell_measurement_theta_min 3.0 _cell_volume 1323.8(7) _computing_cell_refinement CrystalClear _computing_data_collection CrystalClear _computing_data_reduction CrystalStructure _computing_publication_material 'CrystalStructure 3.8' _computing_structure_refinement CRYSTALS _computing_structure_solution SIR97 _diffrn_detector_area_resol_mean 28.57 _diffrn_measured_fraction_theta_full 0.995 _diffrn_measured_fraction_theta_max 0.995 _diffrn_measurement_device_type 'Rigaku Saturn' _diffrn_measurement_method \w _diffrn_radiation_type 'Mo K\a' _diffrn_radiation_wavelength 0.71070 _diffrn_reflns_av_R_equivalents 0.047 _diffrn_reflns_limit_h_max 18 _diffrn_reflns_limit_h_min -18 _diffrn_reflns_limit_k_max 8 _diffrn_reflns_limit_k_min -8 _diffrn_reflns_limit_l_max 19 _diffrn_reflns_limit_l_min -19 _diffrn_reflns_number 20778 _diffrn_reflns_theta_full 27.48 _diffrn_reflns_theta_max 27.48 _exptl_absorpt_coefficient_mu 1.747 _exptl_absorpt_correction_T_max 0.769 _exptl_absorpt_correction_T_min 0.591 _exptl_absorpt_correction_type multi-scan _exptl_absorpt_process_details 'Jacobson, R. (1998) Private communication' _exptl_crystal_colour colorless _exptl_crystal_density_diffrn 1.486 _exptl_crystal_density_method 'not measured' _exptl_crystal_description prism _exptl_crystal_F_000 610.00 _exptl_crystal_size_max 0.20 _exptl_crystal_size_mid 0.20 _exptl_crystal_size_min 0.15 _refine_diff_density_max 1.49 _refine_diff_density_min -1.04 _refine_ls_abs_structure_details 'Flack, H. D. (1983), Acta Cryst. A39, 876-881. 2750 Friedel Pairs' _refine_ls_abs_structure_Flack -0.000(10) _refine_ls_extinction_method none _refine_ls_goodness_of_fit_ref 0.903 _refine_ls_hydrogen_treatment refall _refine_ls_number_parameters 341 _refine_ls_number_reflns 6040 _refine_ls_R_factor_gt 0.0417 _refine_ls_shift/su_max 0.0533 _refine_ls_structure_factor_coef Fsqd _refine_ls_weighting_details 'w = 1/[0.0007Fo^2^ + 1.0000\s(Fo^2^)]/(4Fo^2^)' _refine_ls_weighting_scheme calc _refine_ls_wR_factor_ref 0.1206 _reflns_number_gt 3667 _reflns_number_total 6040 _reflns_threshold_expression F^2^>2.0\s(F^2^) _[local]_cod_data_source_file ol8007556-file001.cif _[local]_cod_data_source_block '_naka070604' _[local]_cod_chemical_formula_sum_orig 'C31 H28 Br O3 S2 ' _cod_original_cell_volume 1323.9(7) _cod_database_code 1504695 loop_ _symmetry_equiv_pos_site_id _symmetry_equiv_pos_as_xyz 1 +X,+Y,+Z 2 -X,1/2+Y,-Z 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 Br(1) Br 0.56014(4) -0.04819(16) 0.34324(4) 0.05777(16) Uani 1.00 1 d . S(1) S -0.07604(8) -0.0415(2) 0.42678(7) 0.0378(2) Uani 1.00 1 d . S(2) S 0.27601(9) 0.7247(2) 0.30412(8) 0.0389(3) Uani 1.00 1 d . O(1) O 0.1813(2) 0.6475(4) 0.2364(2) 0.0348(8) Uani 1.00 1 d . O(2) O 0.2515(2) 0.7745(5) 0.3912(2) 0.0531(11) Uani 1.00 1 d . O(3) O 0.3129(2) 0.8766(4) 0.2497(2) 0.0533(10) Uani 1.00 1 d . C(1) C -0.1653(3) -0.2257(6) 0.3927(2) 0.0314(12) Uani 1.00 1 d . C(2) C -0.2061(3) -0.3585(7) 0.4492(3) 0.0434(14) Uani 1.00 1 d . C(3) C -0.2746(3) -0.4998(8) 0.4078(3) 0.0506(17) Uani 1.00 1 d . C(4) C -0.3001(3) -0.5052(8) 0.3147(3) 0.0463(15) Uani 1.00 1 d . C(5) C -0.2604(3) -0.3716(6) 0.2597(3) 0.0363(13) Uani 1.00 1 d . C(6) C -0.1912(3) -0.2287(6) 0.2964(2) 0.0284(11) Uani 1.00 1 d . C(7) C -0.1378(2) -0.0800(6) 0.2517(2) 0.0269(10) Uani 1.00 1 d . C(8) C -0.0740(3) 0.0268(6) 0.3124(2) 0.0305(11) Uani 1.00 1 d . C(9) C -0.1599(2) -0.0300(8) 0.1506(2) 0.0304(10) Uani 1.00 1 d . C(10) C -0.1572(3) -0.2140(6) 0.0869(3) 0.0312(12) Uani 1.00 1 d . C(11) C -0.2348(3) -0.2633(8) 0.0145(3) 0.0446(14) Uani 1.00 1 d . C(12) C -0.2313(4) -0.4299(8) -0.0425(3) 0.0505(16) Uani 1.00 1 d . C(13) C -0.1482(4) -0.5509(10) -0.0288(2) 0.0549(15) Uani 1.00 1 d . C(14) C -0.0695(4) -0.5074(8) 0.0432(3) 0.0533(17) Uani 1.00 1 d . C(15) C -0.0751(3) -0.3387(7) 0.1008(3) 0.0411(14) Uani 1.00 1 d . C(16) C -0.2559(3) 0.0933(8) 0.1295(3) 0.0512(16) Uani 1.00 1 d . C(17) C -0.0049(2) 0.1875(6) 0.2959(2) 0.0281(11) Uani 1.00 1 d . C(18) C -0.0052(3) 0.3796(6) 0.3372(2) 0.0326(12) Uani 1.00 1 d . C(19) C 0.0582(3) 0.5303(6) 0.3224(2) 0.0310(11) Uani 1.00 1 d . C(20) C 0.1235(2) 0.4880(6) 0.2648(2) 0.0300(11) Uani 1.00 1 d . C(21) C 0.1287(3) 0.2989(7) 0.2240(3) 0.0378(13) Uani 1.00 1 d . C(22) C 0.0641(3) 0.1476(6) 0.2413(3) 0.0350(12) Uani 1.00 1 d . C(23) C 0.3522(3) 0.5075(6) 0.3159(3) 0.0338(12) Uani 1.00 1 d . C(24) C 0.3737(3) 0.4069(7) 0.4007(3) 0.0464(15) Uani 1.00 1 d . C(25) C 0.4358(3) 0.2379(8) 0.4096(3) 0.0470(15) Uani 1.00 1 d . C(26) C 0.4743(3) 0.1787(7) 0.3348(3) 0.0386(13) Uani 1.00 1 d . C(27) C 0.4535(3) 0.2773(8) 0.2515(3) 0.0472(15) Uani 1.00 1 d . C(28) C 0.3915(3) 0.4473(10) 0.2416(3) 0.0441(13) Uani 1.00 1 d . C(29) C 0.5009(8) 0.476(2) 0.0218(5) 0.069(3) Uiso 0.50 1 d P C(30) C 0.5073(10) 0.6645(18) -0.0315(8) 0.074(3) Uiso 0.50 1 d P C(31) C 0.5151(10) 0.3060(18) -0.0431(9) 0.081(4) Uiso 0.50 1 d P H(1) H -0.1881 -0.3528 0.5142 0.053 Uiso 1.00 1 c R H(2) H -0.3034 -0.5932 0.4446 0.063 Uiso 1.00 1 c R H(3) H -0.3464 -0.6034 0.2871 0.056 Uiso 1.00 1 c R H(4) H -0.2807 -0.3772 0.1949 0.044 Uiso 1.00 1 c R H(5) H -0.2912 -0.1795 0.0046 0.053 Uiso 1.00 1 c R H(6) H -0.2841 -0.4605 -0.0901 0.061 Uiso 1.00 1 c R H(7) H -0.1445 -0.6655 -0.0679 0.067 Uiso 1.00 1 c R H(8) H -0.0132 -0.5914 0.0521 0.066 Uiso 1.00 1 c R H(9) H -0.0226 -0.3089 0.1490 0.050 Uiso 1.00 1 c R H(10) H -0.0504 0.4066 0.3769 0.039 Uiso 1.00 1 c R H(11) H 0.0579 0.6609 0.3512 0.036 Uiso 1.00 1 c R H(12) H 0.1745 0.2737 0.1847 0.046 Uiso 1.00 1 c R H(13) H 0.0676 0.0146 0.2155 0.042 Uiso 1.00 1 c R H(14) H 0.3458 0.4521 0.4515 0.056 Uiso 1.00 1 c R H(15) H 0.4512 0.1663 0.4664 0.055 Uiso 1.00 1 c R H(16) H 0.4811 0.2307 0.2007 0.058 Uiso 1.00 1 c R H(17) H 0.3774 0.5195 0.1849 0.053 Uiso 1.00 1 c R H(18) H -0.1074 0.0650 0.1384 0.036 Uiso 1.00 1 c R H(19) H -0.2414 0.2404 0.1365 0.062 Uiso 1.00 1 c R H(20) H -0.2983 0.0525 0.1726 0.062 Uiso 1.00 1 c R H(21) H -0.2884 0.0657 0.0663 0.062 Uiso 1.00 1 c R loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_12 _atom_site_aniso_U_13 _atom_site_aniso_U_23 Br(1) 0.0484(3) 0.0502(3) 0.0709(3) 0.0124(3) -0.0005(2) 0.0008(3) S(1) 0.0421(5) 0.0445(6) 0.0267(5) 0.0036(7) 0.0052(4) -0.0038(6) S(2) 0.0391(6) 0.0286(6) 0.0447(7) -0.0036(5) -0.0048(5) -0.0042(5) O(1) 0.0378(18) 0.0295(17) 0.0339(17) -0.0036(14) -0.0030(14) 0.0024(13) O(2) 0.058(2) 0.049(2) 0.049(2) 0.0035(18) 0.0008(17) -0.0173(17) O(3) 0.053(2) 0.0325(19) 0.070(2) -0.0133(15) -0.0007(18) 0.0091(16) C(1) 0.027(2) 0.035(2) 0.033(2) 0.0066(19) 0.0080(18) 0.0039(19) C(2) 0.050(3) 0.050(3) 0.034(2) 0.013(2) 0.017(2) 0.010(2) C(3) 0.054(3) 0.048(3) 0.057(3) -0.004(2) 0.029(2) 0.011(2) C(4) 0.044(2) 0.050(3) 0.047(2) -0.010(2) 0.014(2) 0.005(2) C(5) 0.036(2) 0.037(2) 0.037(2) 0.002(2) 0.009(2) 0.000(2) C(6) 0.029(2) 0.029(2) 0.027(2) 0.0053(18) 0.0074(17) -0.0012(18) C(7) 0.0245(19) 0.029(2) 0.027(2) 0.0031(18) 0.0036(16) -0.0006(18) C(8) 0.029(2) 0.033(2) 0.030(2) 0.0066(18) 0.0058(18) -0.0020(18) C(9) 0.031(2) 0.028(2) 0.031(2) -0.006(2) 0.0018(16) 0.006(2) C(10) 0.031(2) 0.030(2) 0.034(2) -0.0068(19) 0.0072(19) 0.0077(19) C(11) 0.049(3) 0.045(3) 0.040(2) -0.009(2) 0.007(2) 0.001(2) C(12) 0.060(3) 0.059(3) 0.034(2) -0.016(2) 0.013(2) -0.010(2) C(13) 0.095(4) 0.043(2) 0.030(2) -0.025(3) 0.021(2) -0.010(2) C(14) 0.073(3) 0.039(3) 0.052(3) 0.007(2) 0.023(2) 0.005(2) C(15) 0.054(3) 0.034(2) 0.037(2) 0.002(2) 0.013(2) -0.003(2) C(16) 0.060(3) 0.037(2) 0.057(3) 0.008(2) 0.010(2) 0.011(2) C(17) 0.027(2) 0.026(2) 0.028(2) 0.0012(18) -0.0034(17) -0.0019(18) C(18) 0.033(2) 0.034(2) 0.030(2) 0.011(2) 0.0053(19) -0.0022(18) C(19) 0.036(2) 0.028(2) 0.027(2) 0.0083(19) -0.0016(19) -0.0053(17) C(20) 0.0244(19) 0.032(2) 0.031(2) 0.0036(19) -0.0049(16) -0.0032(19) C(21) 0.035(2) 0.035(2) 0.045(2) 0.002(2) 0.011(2) -0.010(2) C(22) 0.033(2) 0.026(2) 0.048(2) 0.0011(19) 0.010(2) -0.012(2) C(23) 0.029(2) 0.031(2) 0.039(2) -0.0084(18) -0.0014(19) 0.001(2) C(24) 0.050(2) 0.049(3) 0.040(2) -0.000(2) 0.007(2) -0.005(2) C(25) 0.048(3) 0.046(3) 0.044(2) 0.005(2) -0.002(2) 0.011(2) C(26) 0.030(2) 0.036(2) 0.047(2) -0.005(2) -0.001(2) -0.001(2) C(27) 0.046(2) 0.050(3) 0.049(3) 0.002(2) 0.019(2) 0.002(2) C(28) 0.046(2) 0.046(2) 0.042(2) 0.004(3) 0.010(2) 0.004(3) loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.003 0.002 ; International Tables for Crystallography (1992, Vol. C, Tables 4.2.6.8 and 6.1.1.4) ; H H 0.000 0.000 ; International Tables for Crystallography (1992, Vol. C, Table 6.1.1.4) ; O O 0.011 0.006 ; International Tables for Crystallography (1992, Vol. C, Tables 4.2.6.8 and 6.1.1.4) ; S S 0.125 0.123 ; International Tables for Crystallography (1992, Vol. C, Tables 4.2.6.8 and 6.1.1.4) ; Br Br -0.290 2.459 ; International Tables for Crystallography (1992, Vol. C, Tables 4.2.6.8 and 6.1.1.4) ; loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_publ_flag _geom_angle_site_symmetry_3 C(1) S(1) C(8) 91.5(2) yes . O(1) S(2) O(2) 109.39(19) yes . O(1) S(2) O(3) 102.02(18) yes . O(1) S(2) C(23) 103.46(18) yes . O(2) S(2) O(3) 121.2(2) yes . O(2) S(2) C(23) 109.3(2) yes . O(3) S(2) C(23) 109.8(2) yes . S(2) O(1) C(20) 119.9(2) yes . S(1) C(1) C(2) 127.1(3) yes . S(1) C(1) C(6) 110.4(3) yes . C(2) C(1) C(6) 122.5(3) yes . C(1) C(2) C(3) 118.1(4) yes . C(2) C(3) C(4) 120.1(5) yes . C(3) C(4) C(5) 121.3(4) yes . C(4) C(5) C(6) 121.5(4) yes . C(1) C(6) C(5) 116.5(4) yes . C(1) C(6) C(7) 112.8(3) yes . C(5) C(6) C(7) 130.7(3) yes . C(6) C(7) C(8) 112.2(3) yes . C(6) C(7) C(9) 124.1(3) yes . C(8) C(7) C(9) 123.2(3) yes . S(1) C(8) C(7) 113.0(3) yes . S(1) C(8) C(17) 117.4(2) yes . C(7) C(8) C(17) 129.6(3) yes . C(7) C(9) C(10) 114.7(3) yes . C(7) C(9) C(16) 109.5(3) yes . C(10) C(9) C(16) 113.2(3) yes . C(9) C(10) C(11) 122.8(3) yes . C(9) C(10) C(15) 118.2(3) yes . C(11) C(10) C(15) 118.9(4) yes . C(10) C(11) C(12) 122.1(4) yes . C(11) C(12) C(13) 118.3(4) yes . C(12) C(13) C(14) 121.2(5) yes . C(13) C(14) C(15) 119.5(5) yes . C(10) C(15) C(14) 119.9(4) yes . C(8) C(17) C(18) 120.9(3) yes . C(8) C(17) C(22) 120.5(3) yes . C(18) C(17) C(22) 118.6(4) yes . C(17) C(18) C(19) 121.6(4) yes . C(18) C(19) C(20) 118.3(4) yes . O(1) C(20) C(19) 120.5(3) yes . O(1) C(20) C(21) 116.5(3) yes . C(19) C(20) C(21) 122.6(4) yes . C(20) C(21) C(22) 117.8(4) yes . C(17) C(22) C(21) 121.1(4) yes . S(2) C(23) C(24) 119.8(3) yes . S(2) C(23) C(28) 118.2(3) yes . C(24) C(23) C(28) 122.0(4) yes . C(23) C(24) C(25) 119.2(4) yes . C(24) C(25) C(26) 118.3(4) yes . Br(1) C(26) C(25) 120.1(3) yes . Br(1) C(26) C(27) 117.2(3) yes . C(25) C(26) C(27) 122.7(4) yes . C(26) C(27) C(28) 119.6(4) yes . C(23) C(28) C(27) 118.2(4) yes . C(30) C(29) C(31) 104.3(9) yes . C(29) C(30) C(31) 94.5(10) yes 2_655 C(29) C(31) C(30) 85.3(10) yes 2_645 C(1) C(2) H(1) 121.1(5) no . C(3) C(2) H(1) 120.8(6) no . C(2) C(3) H(2) 120.0(5) no . C(4) C(3) H(2) 119.9(5) no . C(3) C(4) H(3) 119.4(6) no . C(5) C(4) H(3) 119.3(5) no . C(4) C(5) H(4) 119.3(5) no . C(6) C(5) H(4) 119.2(5) no . C(7) C(9) H(18) 106.2 no . C(10) C(9) H(18) 106.1 no . C(16) C(9) H(18) 106.5 no . C(10) C(11) H(5) 119.5(5) no . C(12) C(11) H(5) 118.3(5) no . C(11) C(12) H(6) 120.7(6) no . C(13) C(12) H(6) 121.0(6) no . C(12) C(13) H(7) 119.3(5) no . C(14) C(13) H(7) 119.5(6) no . C(13) C(14) H(8) 120.5(5) no . C(15) C(14) H(8) 119.9(5) no . C(10) C(15) H(9) 120.3(5) no . C(14) C(15) H(9) 119.9(5) no . C(9) C(16) H(19) 109.1 no . C(9) C(16) H(20) 109.4 no . C(9) C(16) H(21) 109.9 no . H(19) C(16) H(20) 109.5 no . H(19) C(16) H(21) 109.5 no . H(20) C(16) H(21) 109.5 no . C(17) C(18) H(10) 119.3(5) no . C(19) C(18) H(10) 119.1(4) no . C(18) C(19) H(11) 121.1(5) no . C(20) C(19) H(11) 120.6(5) no . C(20) C(21) H(12) 120.9(5) no . C(22) C(21) H(12) 121.3(5) no . C(17) C(22) H(13) 119.5(5) no . C(21) C(22) H(13) 119.4(5) no . C(23) C(24) H(14) 120.5(5) no . C(25) C(24) H(14) 120.3(5) no . C(24) C(25) H(15) 120.8(6) no . C(26) C(25) H(15) 120.9(6) no . C(26) C(27) H(16) 120.3(5) no . C(28) C(27) H(16) 120.1(5) no . C(23) C(28) H(17) 120.9(6) no . C(27) C(28) H(17) 120.8(6) no . loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_publ_flag _geom_bond_site_symmetry_2 Br(1) C(26) 1.894(4) yes . S(1) C(1) 1.742(4) yes . S(1) C(8) 1.749(4) yes . S(2) O(1) 1.598(3) yes . S(2) O(2) 1.423(3) yes . S(2) O(3) 1.424(3) yes . S(2) C(23) 1.761(4) yes . O(1) C(20) 1.423(5) yes . C(1) C(2) 1.390(6) yes . C(1) C(6) 1.404(5) yes . C(2) C(3) 1.391(7) yes . C(3) C(4) 1.359(7) yes . C(4) C(5) 1.370(7) yes . C(5) C(6) 1.385(5) yes . C(6) C(7) 1.448(6) yes . C(7) C(8) 1.345(5) yes . C(7) C(9) 1.506(5) yes . C(8) C(17) 1.474(6) yes . C(9) C(10) 1.526(6) yes . C(9) C(16) 1.550(6) yes . C(10) C(11) 1.423(6) yes . C(10) C(15) 1.394(6) yes . C(11) C(12) 1.377(7) yes . C(12) C(13) 1.390(8) yes . C(13) C(14) 1.421(6) yes . C(14) C(15) 1.398(7) yes . C(17) C(18) 1.390(5) yes . C(17) C(22) 1.385(6) yes . C(18) C(19) 1.365(6) yes . C(19) C(20) 1.379(6) yes . C(20) C(21) 1.377(6) yes . C(21) C(22) 1.390(6) yes . C(23) C(24) 1.397(6) yes . C(23) C(28) 1.365(6) yes . C(24) C(25) 1.395(7) yes . C(25) C(26) 1.364(7) yes . C(26) C(27) 1.372(7) yes . C(27) C(28) 1.399(7) yes . C(29) C(30) 1.467(17) yes . C(29) C(31) 1.499(17) yes . C(30) C(31) 1.508(19) yes 2_655 C(2) H(1) 0.950(6) no . C(3) H(2) 0.950(7) no . C(4) H(3) 0.950(6) no . C(5) H(4) 0.950(6) no . C(9) H(18) 1.000 no . C(11) H(5) 0.950(7) no . C(12) H(6) 0.950(7) no . C(13) H(7) 0.950(8) no . C(14) H(8) 0.950(7) no . C(15) H(9) 0.950(6) no . C(16) H(19) 0.980 no . C(16) H(20) 0.980 no . C(16) H(21) 0.980 no . C(18) H(10) 0.950(6) no . C(19) H(11) 0.950(6) no . C(21) H(12) 0.950(7) no . C(22) H(13) 0.950(6) no . C(24) H(14) 0.950(7) no . C(25) H(15) 0.950(7) no . C(27) H(16) 0.950(7) no . C(28) H(17) 0.950(7) no . _journal_paper_doi 10.1021/ol8007556