A Catalyst-Free Facile Synthesis of 2-(dihydropyridyl)benzothiazoles from (Benzothiazol-2-yl)acrylonitriles: A Green Route
Singh, Nikunj; Budhwan, Rajnish; Rawat, Megha; Peddinti, Rama Krishna; Organic & Biomolecular Chemistry  (2025) –; doi:10.1039/D6OB00288A

data_7161080
_publ_section_title
;
 Catalyst-free facile synthesis of 2-(dihydropyridyl)benzothiazoles from
 (benzothiazol-2-yl)acrylonitriles: green route.
;
_journal_issue                   15
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3210
_journal_page_last               3217
_journal_paper_doi               10.1039/d6ob00288a
_journal_volume                  24
_journal_year                    2026
_chemical_formula_moiety         '0.129(C28 H25 N5 O2 S)'
_chemical_formula_sum            'C3.61 H3.23 N0.65 O0.26 S0.13'
_chemical_formula_weight         63.95
_chemical_name_systematic        RKP_NS_31_2000
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     dual
_audit_creation_date             2025-10-27
_audit_creation_method
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_audit_update_record
;
2025-10-27 deposited with the CCDC.	2026-03-18 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            31
_cell_length_a                   8.499(3)
_cell_length_b                   15.707(6)
_cell_length_c                   18.184(7)
_cell_measurement_reflns_used    9917
_cell_measurement_temperature    100.00
_cell_measurement_theta_max      25.8405
_cell_measurement_theta_min      2.4346
_cell_volume                     2427.5(16)
_computing_cell_refinement       'SAINT V8.40B (?, 2016)'
_computing_data_reduction        'SAINT V8.40B (?, 2016)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL  (Sheldrick, 2008)'
_computing_structure_solution    'XT  (Sheldrick, 2015)'
_diffrn_ambient_temperature      100.00
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.980
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1281
_diffrn_reflns_av_unetI/netI     0.1575
_diffrn_reflns_Laue_measured_fraction_full 0.993
_diffrn_reflns_Laue_measured_fraction_max 0.980
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            37086
_diffrn_reflns_point_group_measured_fraction_full 0.987
_diffrn_reflns_point_group_measured_fraction_max 0.957
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         29.555
_diffrn_reflns_theta_min         2.240
_diffrn_source_current           1.4
_diffrn_source_power             0.07
_diffrn_source_voltage           50.0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.170
_exptl_absorpt_correction_T_max  0.7459
_exptl_absorpt_correction_T_min  0.1563
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1864 before and 0.1295 after correction.
The Ratio of minimum to maximum transmission is 0.2095.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear orangish orange'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   orangish
_exptl_crystal_colour_primary    orange
_exptl_crystal_density_diffrn    1.356
_exptl_crystal_description       block
_exptl_crystal_F_000             1040
_exptl_crystal_size_max          0.166
_exptl_crystal_size_mid          0.138
_exptl_crystal_size_min          0.082
_refine_diff_density_max         0.511
_refine_diff_density_min         -0.985
_refine_diff_density_rms         0.104
_refine_ls_abs_structure_details
;
 Flack x determined using 2278 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.18(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.989
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     653
_refine_ls_number_reflns         13036
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.989
_refine_ls_R_factor_all          0.1372
_refine_ls_R_factor_gt           0.0957
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1331P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2258
_refine_ls_wR_factor_ref         0.2626
_reflns_Friedel_coverage         0.888
_reflns_Friedel_fraction_full    0.980
_reflns_Friedel_fraction_max     0.932
_reflns_number_gt                7870
_reflns_number_total             13036
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6ob00288a2.cif
_cod_data_source_block           rkp_ns_31_2000_0ma
_cod_depositor_comments
'Adding full bibliography for 7161079--7161081.cif.'
_cod_original_cell_volume        2427.4(17)
_cod_database_code               7161080
_shelx_shelxl_version_number     2019/1
_shelx_estimated_absorpt_t_max   0.986
_shelx_estimated_absorpt_t_min   0.972
_olex2_refinement_description
;
1.a Rotating group:
 N008(H00A,H00B), N(HA,HB)
1.b Ternary CH refined with riding coordinates:
 C00O(H00O), C00W(H00W)
1.c Secondary CH2 refined with riding coordinates:
 C00M(H00E,H00F), C00V(H00C,H00D), C016(H01J,H01K), C019(H01M,H01O), C01A(H01A,
 H01B), C01H(H01D,H01E), C01K(H01Y,H), C01O(H01H,H01I)
1.d Aromatic/amide H refined with riding coordinates:
 C00U(H00U), C010(H010), C011(H011), C014(H014), C015(H015), C017(H017),
 C018(H018), C01C(H01C), C01D(H01R), C01E(H01S), C01F(H01F), C01G(H01G),
 C01I(H01U), C01J(H01X), C01L(H01L), C01M(H01Z), C01N(H01N), C01P(H01P),
 C01Q(H01Q), C01S(H01), C01T(H01T), C01U(H1), C01V(H01V), C01W(H01W), C01X(H2),
 C01Y(H3), C01Z(H4), C020(H020)
;
_shelx_res_checksum              25455
_olex2_submission_special_instructions 'No special instructions were received'