Starting from sodium carbomethoxycyclopentadienide, diphenylacetylene, and chlorotris(triphenylphosphine)cobalt(I), the title compound was obtained in four steps and 47% overall yield. On reaction with Pd(OAc) 2 , a single cyclopalladated diastereoisomer of (S)-( p R) configuration was isolated in 72% yield.

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This article develops a stationary cardiac single photon emission computed tomography ͑SPECT͒ system using a novel multidivergent-beam collimator. This stationary SPECT system is inexpensive to build, small, and able to acquire true dynamic SPECT data. Stationary cardiac SPECT systems with multipinhole technology already exist. The proposed approach is to replace the multipinhole collimators with the originally designed multidivergent-beam collimators. The motivation for replacing the pinhole technology by divergent-beam technology is based on the following facts. The resolution/sensitivity trade-off for the pinhole is excellent ͑good resolution and good sensitivity͒ only in small object ͑e.g., small animal͒ imaging when it operates in the image magnifying mode. However, in large object ͑e.g., human͒ imaging, the resolution/sensitivity trade-off is poor ͑poor resolution and poor sensitivity͒ when the pinhole operates in the image reducing mode. In a stationary system, the number of angular views is limited; thus, image reduction is necessary to obtain more view angles. In this image reducing situation, divergent-beam collimation is able to provide better resolution and detection sensitivity than pinhole collimation. Computer simulations are carried out to verified the claims.