Mitsunobu reaction of an alcohol ROH with a carboxylic acid, phthalimide, or N-hydroxyphthalimide (NuH) using DNAD (4) and (diphenylphosphino)polystyrene (11) gave the products RNu. Ring-opening metathetic polymerization of the side product DNADH(2) (3) using Cl(2)(Cy(3)P)(2)Ru=CHPh (13) and filtration, to remove poly(DNADH(2)), (diphenylphosphino)polystyrene 11, its oxide, and its adduct with excess DNAD, gave RNu (43-100%, 86-96% purity) without recourse to chromatography.
The regio-and stereoselective synthesis of the protected cis-3-aminooxetanes cis-5 and cis-7 is reported. The oxetanes were obtained by the photocycloaddition of aliphatic (6c-e) and aromatic (4, 6a) aldehydes to the corresponding enamides (1a-d,h) or enecarbamates (1e-g). The enamine derivatives used in the Paterno `-Bu ¨chi reaction were either commercially available or prepared from the corresponding acetaldehyde imines 2 by acylation. The oxetane formation proceeded with good-to-excellent simple diastereoselectivity for aromatic aldehydes (56-82% yield) and moderate selectivity for aliphatic aldehydes (46-55% yield). The cis-3-aminooxetanes are precursors for synand anti-1,2-amino alcohols. The relative configuration established in the photochemical step was retained upon nucleophilic ring opening between the oxygen atom and carbon atom C-4. By this means, syn-1,2-amino alcohols such as 8 and 10 were available in good yields. In contrast, the N-Boc-protected cis-3-aminooxetanes cis-5e and cis-5f were transformed into anti-1,2-amino alcohols. Upon treatment with trifluoroacetic acid, they underwent an intramolecular nucleophilic substitution at the carbon atom C-2 of the oxetane and the oxazolidinones 11 and 12 were formed. Because the substitution occurs with inversion of configuration, anti-1,2-amino alcohols, e.g., ephedrine (15), are accessible.
The graduate employment market faces ever-increasing socioeconomic and political pressures. Higher Education Institutions and the sport sector in the EU have an important role in contributing to graduate employment. The aims of the study were: (1) to assess general perceptions of employability, and (2) to assess sports graduates' and employers' perceptions of specific capabilities and competencies in order to identify possible improvements for sports graduate employability programmes. A cross sectional survey of sports graduates and employers was administered in six EU countries including the UK, France, Germany, Spain, Greece and the Czech Republic to assess graduate and employer perceptions. A graduate capabilities and competencies framework was devised to assess personal, interpersonal, cognitive, role-specific and generic skills. Responses were elicited from 1,132 sports graduates and 327 employers. There was generally a wide difference of opinion between employers and sports graduates in terms of the importance and possession of a number of capabilities and competencies. There is a need for the Higher Education sector and employers to take responsibility in ensuring that work experience, work placement and volunteering opportunities are embedded in curricula and to ensure the fitness of purpose of what and how graduate capabilities and competencies are assessed.
The antibiotic β‐amino acid oxetin (rac‐1) has been prepared by the stereoselective Paternò‐B üchi reaction of enecarbamate 2 and n‐butyl glyoxylate (5). The overall yield of the four‐step synthesis is 14%. The order of the deprotection steps proved to be important in minimizing possible side reactions.
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