The crystal was mounted
and centered on a Bruker SMART APEX system.
The radiation used was Mo Kα (λ = 0.71073 A, m = 4.413 mm–1). Rotation and still images showed
diffractions to be sharp, while frames separated in reciprocal space
were obtained and provided an orientation matrix and initial cell
parameters. Final cell parameters were obtained from the full data
set. A “hemisphere” data set was obtained, which samples
approximately 1.2 hemispheres of reciprocal space to a resolution
of 0.84 Å using 0.3 degree steps in ω and using 10 s interval
times for each frame. Absorption corrections were applied using SADABS
(references of all software and sources of scattering factors are
contained in the SHELXTL (version 5.1) program library, G. Sheldrick,
Bruker Analytical X-ray Systems, Madison, WI, USA). The space group
was determined based on systematic absences and intensity statistics.
Direct or Patterson methods were used to locate the heavy atoms, C
atoms, and all other heteroatoms from the E-map. Repeated difference
Fourier maps allowed recognition of all expected H atoms. Prior to
location of H, other atoms were converted to and refined anisotropically.
Hydrogen atoms were refined isotropically and were placed in calculated
(dCH = 0.96 Å) positions. Structures
were collected at 100 K. Crystal data and structure analysis results
are shown in theSupporting Information .
and centered on a Bruker SMART APEX system.
The radiation used was Mo Kα (λ = 0.71073 A, m = 4.413 mm–1). Rotation and still images showed
diffractions to be sharp, while frames separated in reciprocal space
were obtained and provided an orientation matrix and initial cell
parameters. Final cell parameters were obtained from the full data
set. A “hemisphere” data set was obtained, which samples
approximately 1.2 hemispheres of reciprocal space to a resolution
of 0.84 Å using 0.3 degree steps in ω and using 10 s interval
times for each frame. Absorption corrections were applied using SADABS
(references of all software and sources of scattering factors are
contained in the SHELXTL (version 5.1) program library, G. Sheldrick,
Bruker Analytical X-ray Systems, Madison, WI, USA). The space group
was determined based on systematic absences and intensity statistics.
Direct or Patterson methods were used to locate the heavy atoms, C
atoms, and all other heteroatoms from the E-map. Repeated difference
Fourier maps allowed recognition of all expected H atoms. Prior to
location of H, other atoms were converted to and refined anisotropically.
Hydrogen atoms were refined isotropically and were placed in calculated
(dCH = 0.96 Å) positions. Structures
were collected at 100 K. Crystal data and structure analysis results
are shown in the