The course design "Training OC" for training the application of basic concepts consists of four topics: formula language, structure−property relations, reaction mechanisms, and complex tasks that the students should solve with the conceptual knowledge they acquired in the first three topics. A main goal of the course was to enable the students to solve reaction mechanisms. To achieve the goals of the course, several games were specially designed and used. The course was conducted at a German university with ca. 30 students who participated voluntarily. The course was evaluated by several tools: students' products were collected in the course, there were two pre/post-tests, and additionally, interviews on the strategy of designing reaction mechanisms were conducted. The performance of the teacher and the self-assessment of the students were also part of the evaluation. The results of the written exam were compared with the results of the bachelor chemistry major students. The course "Training OC" was rated very well by the students. They were of the opinion that they learned the application of basic concepts taught in this course. This is supported by the results of the evaluation and the written exams. The course concept of Training OC will therefore become a permanent part of the course "Organic Chemistry I" which will be redesigned for the next round in 2020−21.

Stepped supporting tools were developed and used in the university seminar Organic Chemistry taken by nonmajor chemistry students, which supported self-regulated learning. These supporting tools were also used for accompanying homework, which included a QR code that led to additional supporting tools. The application of stepped supporting tools in the seminars was evaluated by a four-item Likert scale. The students assessed the tools as a helpful instrument for solving tasks in chemistry.

In this article the development, use and evaluation of tasks in organic chemistry is discussed. These tasks are designed following the concept of school-related content knowledge. In this study the perceived relevance of these new tasks by preservice chemistry teachers was evaluated. Of special interest was the question how new tasks should be designed to be perceived as relevant; are some features of the tasks more suitable than others? To answer all research questions a mixed methods study was conducted. To understand the students’ rating of the new tasks by using questionnaires, in addition focus group interviews were conducted. The suitability of these new tasks for use in written exams was also evaluated. The results show that the students perceived the tasks as relevant for their future profession if they included contents of the school curriculum, realistic situations and were personalized. They perceived the new tasks also as relevant for practicing skills in communication and explanations.

Educational Scaffolding was first mentioned in 1976 by Wood et al. Several examples for scaffolding in chemistry are also known from the literature. As written scaffolds, stepped supporting tools to support students while solving problems in organic chemistry were developed, applied, and evaluated. Although the students rated the tool as very helpful, a think-aloud study showed that the support given by this scaffold was not sufficient. As a further development of stepped supporting tools, task navigators were therefore developed, applied, and evaluated. This new scaffold gives tips on strategy, knowledge, and application of knowledge after the STRAKNAP concept. The evaluation of this tool shows that the students rated the tool as being very helpful. A think-aloud study showed that the scaffold supports the students while they solve a problem. Because of the stepwise construction of the task navigators and the providing of the knowledge needed for the application, the students can solve parts of the task successfully even if they do not solve all parts correctly; the students can always start from scratch. When students use the tool regularly, their knowledge of organic chemistry increases compared to students who did not use the tool at all. The task navigator is not only a scaffold for the content of the task but also for the development of methodological competences on the field of strategies and applying knowledge.

In this article a cross-sectional study on the students’ rating with regard to the contents in organic chemistry will be discussed. Pre-service teachers rated the contents with a questionnaire during their bachelor or master studies. It was shown that the pre-service chemistry teachers during their master studies rated the content as more important than the bachelor students. One possible explanation can be that the master students have teaching experience due to their internships at school whereas the bachelor students can only rely on their experience from their own school days. Overall, content belonging to the school curriculum in the federal state “Brandenburg” where the pre-service teachers’ university is located was rated better than content that was not a part of this curriculum. Concepts were not rated significantly better than the content. Because of the importance of conceptual knowledge for the future profession as a teacher, the courses in organic chemistry will be redesigned with a clear focus on concepts.

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In this paper the development, use, and evaluation of tasks based on the construct of school-related content knowledge are described. The tasks were used in seminars on organic chemistry for bachelor and master preservice chemistry teachers at a German university. For the evaluation a questionnaire with open and closed items was used. The tasks were rated by the preservice chemistry teachers as relevant for their future profession as a chemistry teacher if the content of the tasks is part of the school curriculum. If the content does not belong to the school curriculum, they rated the nature of the tasks still as relevant; they seem to recognize the importance of conceptual knowledge for their future profession. However, the master's preservice teachers argued with this conceptual knowledge more often than the bachelor's preservice teachers. Although the study is cross-sectional, a certain shift from the focus on the content to conceptual knowledge from bachelor's to master's preservice teachers can be observed.

In most cases where ring closing metathesis is applied to the synthesis of heterocycles, α,ω-dienes are used as precursors. If substrates containing more than two double bonds are subjected to a metathesis reaction, carba-or heterocycles bearing additional exocyclic alkene functionality result, or multiple ring closing processes occur. This offers interesting and potentially very useful synthetic perspectives. On the other hand, selectivity problems need to be addressed as the cyclization of substrates with more than two double bonds available for olefin metathesis may result in constitutional isomers or stereoisomers. This review highlights problems and opportunities evolving from ring closing metathesis of tri-, tetra-, and polyenes as a strategy for the selective synthesis of functionalized heterocycles. The chapter on RCM of trienes is subdivided according to the symmetry of the metathesis precursor. The following two chapters deal with the double or multiple RCM of tetra-or polyenes. These processes are further classified according to the preferred cyclization mode. Finally, the application of cascade or domino metathesis reactions to the synthesis of heterocycles will be discussed. These processes can be classified into those where exclusively C-C-double bonds take part in the metathesis reaction, and those where one or more C-C-triple bonds are involved.