Stereospecific Conversion of Boronic Esters into Enones using Methoxyallene: Application in the Total Synthesis of 10-Deoxymethynolide.

Enones are widely utilized linchpin functional groups in chemical synthesis and molecular biology. We herein report the direct conversion of boronic esters into enones using commercially available methoxyallene as a three-carbon building block. Following boronate complex formation by reaction of the boronic ester with lithiated-methoxyallene, protonation triggers a stereospecific 1,2-migration before oxidation generates the enone. The protocol shows broad substrate scope and complete enantiospecificity is observed with chiral migrating groups. In addition, various electrophiles could be used to induce 1,2-migration and give a much broader range of α-functionalized enones. Finally, the methodology was applied to a 14-step synthesis of the enone-containing polyketide 10-deoxymethynolide.

Reflexivity and habitus: opportunities and constraints on transformative learning.

This paper will explore the relationship between Mezirow's concept of reflexivity and Bourdieu's theory of habitus in order to develop a more robust framework within which critical reflection can take place. Nurse educators have sought to close the theory practice gap through the use of critical reflection. However, we are not convinced that this has produced the depth and quality of reflection required. Furthermore, the contexts in which critical reflection takes place is often sidelined or erased so that the whole impetus in the literature is to educate nurses in reflection rather than empower nurses to understand the complex circumstances and barriers that obstruct critical reflection. This paper argues that the reason for this position is that nurse education does not always acknowledge the role that personal and cultural values systems have on reflective practices. The literature search was undertaken using CINHAL and MEDLINE. Keywords included: values systems, habitus, and critical reflection. Inclusion criteria were determined by the theoretical approach and included seminal texts, from as far back as 1956, to identify key themes. Although critical reflection is a potentially powerful way of enhancing care it has often failed to do so. It is suggested that this is because nurse educators have frequently used models of reflection without considering the impact that student's personal values systems has on their perceptions of care and subsequently care delivery. The purpose of this paper is to promote deeper levels of reflection and is part of a programme of research aimed at developing a more robust approach to reflection in educational practice.