41. A suprafacial transformation at a chiral center preserves stereochemistry, whereas an antarafacial transformation reverses stereochemistry . 42. There are exceptions to this pattern, some of which indicate stereochemistry ( PGF 2? ). 43. His 1962 textbook " Stereochemistry of Carbon Compounds " influenced generations of organic chemists. 44. "' Mechanostereochemistry "'is the stereochemistry of the molecules with mechanical bonds. 45. This can affect both the kinetics of the reaction and the stereochemistry of the reaction products. 46. It seems to me that possibly in such transitions you could have stereochemistry -affecting effects. 47. Catalytic cycle of the Catellani reaction . ( Ligands and stereochemistry are omitted for clarity .) 48. This creates the demand for'stereoselective synthesis', producing a compound with a defined stereochemistry . 49. Bromination and iodination work best, though this reaction does not preserve the stereochemistry of the alcohol. 50. The stereochemistry of R 1 and R 2 in the cycloaddition product is derived from the dipole.
