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Palladium(II)-coordinated NCR¹ (R¹ = Et ( 1 ), NMe2 (2), Ph (3)) species react smoothly with acyclic nitrones such as the ketonitrones Ph2C=N(O)R⁴ (R⁴ = p-MeC6H4 (4), p-ClC6H4 (5)) and the aldonitrone p- MeC6H4CH=N(O)Me (6) in the corresponding nitrile media. This reaction proceeds as a consecutive two-step intennolecular cycloaddition to give the mono- and bis-2,3-dihydro-1,2,4-oxadiazole complexes [PdCl2(R¹CN){Na= C(R¹)ON(R⁴)Cb(R²R³)}](a-b) (7a-13a; R², R³ = Ph; R⁴ = C6H4Me-p, R¹ = Et (7), NMe2 (8), Ph (9); R⁴ = C6H4Cl-p, R¹ = Et (10), NMe2 (11), Ph (12); R² = H, R³ = C6H4Me-p, R4 = Me, R¹ = NMe2 (13)) and [PdCl2{Na= C(R¹)ON(R⁴)Cb(R²R³)}2](a-b) (7b-13b), respectively. Inspection of the obtained data and their comparison with the previous results indicate that the PdII centers provide substantially greater activation of RCN ligands toward the 1,3-dipolar cycloaddition than the relevant PtII centers. The palladium(II)- mediated 1,3-dipolar cydoaddition of ketonitrones to nitriles is reversible. All complexes were characterized by elemental analyses (C, H, N), high-resolution ESI-MS, and IR and ¹H and 13C{¹H} NMR spectroscopy. The structure of trans- 7b was determined by single-crystal X-ray diffraction. Metal-free 5-NR'2-2,3- dihydro-1,2,4-oxadiazoles (7c--13c) were liberated from the corresponding (2,3-dihydro-1,2,4-oxadiazole)2PdII complexes by treatment with 1,2-(diphenylphosphino)ethane, and the heterocycles were characterized by high-resolution ESI⁺-MS and ¹H and 13C{¹H} spectroscopy. [ABSTRACT FROM AUTHOR]

The study describes the demographic details and smear results of women attending a Well Woman Clinic in an Occupational Health setting over a two year period. The clinic is located close to the place of work, run during working hours, and operated by a doctor and nurse. Charging fees acceptable to women attending or their employers, the service has made a modest profit and offers scope for increasing the income against fixed costs. The age range attending is older than commonly found at screening clinics. The abnormal smear detection rate, 115 per 1000 is high while the proportion of inadequate results at 50 per 1000 compares favourably with other clinics. In an area with 13 per cent Asian population, only 5 per cent of attenders were Asian but of these one fifth had abnormal smears. A cervical cytology screening facility timed and located for the convenience of the working woman is found to attract a group of women in the older age range who have a high abnormal smear rate, and those who fail to attend elsewhere.