Nazarov reactions of 2-furyl vinyl ketones and related heteroaromatic enones, to produce furan-fused cyclopentanones using a flow photochemical approach, are described. Compounds possessing this connectivity between heterocycle and ketone (2-furyl, 2-benzofuryl, 2-thiophene-yl, and 2-benzothiophene-yl) have traditionally proven difficult or impossible to cyclize with typical Brønsted and Lewis acid mediated methods. Using mild flow photochemistry conditions and acetic acid (AcOH) or hexafluoroisopropanol (HFIP) as solvent, these compounds were found to cyclize in 45-97% yields, with typical UV exposure times of 3.4-6.8 min. In all cases, 2-furyl and 2-thiophene-yl enones cyclized, whereas 2-benzofuryl and 2-benzothiophene-yl enones exhibited divergent properties with reactivity patterns tied to the identity of the vinyl group. This report discloses the first photo-Nazarov reactions of tetrahydropyridine-substituted 2-furyl ketones, providing a direct approach to the corresponding fused heterocyclic motifs built around a central cyclopentanone. These motifs constitute the core structures of biologically active natural products, including the marine alkaloid nakadomarin A.
Millions of workers, finding themselves displaced from their original occupations, are not prepared to plan and develop new work lives. Adult career counseling can prouide them with the skills needed to take charge of their career futures.During the 1980s, large-scale worker displacement has been a pervasive and often economically devastating problem for millions of Americans.As the economy has improved, some of these workers have found new jobs, though often at lower wages and involving work quite different from their previous occupations. Displaced workers, in transition from an extended period of unemployment to full-time work, need to adjust to new job tasks, supervisors, co-workers, company policies, schedules, and routines as well as decreased wages and benefits. In addition to job-related adjustments, many workers who have been forced to change occupations must also adjust to changes in their family and life circumstances.Coping with the challenges that accompany forced occupational change often demands life-and career-planning skills that many adults have not developed. In particular, workers who have been with a single employer for years and who have depended on a union to negotiate their job futures often feel lost when they become displaced. People who grew up with the idea that after high school they would go to work in the local mill had little reason or opportunity to develop life-or career-planning skills.Displaced workers may receive employment assistance such as training in job-search techniques, resumd preparation, and interview skills New Directions for Continuing Edocation. no. 52. San Francisco: Josrey-Bass. Winter 1986. 71 J. V. Miller, M. L. Musgrove (4s.). I m s in Adult Curcn Counrcling.
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