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Photocatalytic reactions involving a reductive radical‐polar crossover (RRPCO) generate intermediates with carbanionic reactivity. Many of these proposed intermediates resemble highly reactive organometallic compounds. However, conditions of their formation are generally not tolerated by their isolated organometallic versions and often a different reactivity is observed. Our investigations on their nature and reactivity under commonly used photocatalytic conditions demonstrate that these intermediates are indeed best described as free, superbasic carbanions capable of deprotonating common polar solvents usually assumed to be inert such as acetonitrile, dimethylformamide, and dimethylsulfoxide. Their basicity not only towards solvents but also towards electrophiles, such as aldehydes, ketones, and esters, is comparable to the reactivity of isolated carbanions in the gas‐phase. Previously unsuccessful transformations thought to result from a lack of reactivity are explained by their high reactivity towards the solvent and weakly acidic protons of reaction partners. An intuitive explanation for the mode of action of photocatalytically generated carbanions is provided, which enables methods to verify reaction mechanisms proposed to involve an RRPCO step and to identify the reasons for the limitations of current methods. [ABSTRACT FROM AUTHOR]

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The Chronica Boemorum, written by Prague's Dean Cosmas, plays a pivotal, crucial role in studying the early medieval history of the Czech lands. However, the uniqueness of the work is matched by the range of problems associated with its interpretation. In 1967, when František Graus published a study in the "Československý časopis historický" dedicated to the topic of the so-called "Necrologium Bohemicum" and "Martyrologium Pragense", accompanied by the subtitle "Traces of a Non-Cosma's Conception of Czech History", it seemed that a entirely new chapter in the field of domestic medieval studies was about to commence. The Necrologium, or rather the commemoration of persons hostile to the ruling House of Přemyslid, preserved here, was to be not only a proof of the bias of the chronicler Cosmas but also of the existence of a contemporary different, "unofficial" opinion towards the events depicted in his work. Although Graus devoted only a small part of his study to the problems outlined, it was the subtitle and especially the phrase "non-Cosma's conception" that became the key message of the text, which seemed to offer new possibilities of studying older Czech history. An approach that was to have the potential to at least partially liberate research from the single and unique narrative of Cosmas, which for a large part of domestic early medieval history lacked any similar counterpart and corrective. The "non-Cosma's conception" took even up to the form of a methodical approach, revealing and reconstructing history and historical events, whether unintentionally or intentionally, hidden or distorted by the Dean. The following study not only returns to Graus's initial premise, but also tries to point out the actual problem of the "Cosma's conception" as a starting point for considering the existence of the "non-Cosma' s" one. [ABSTRACT FROM AUTHOR]

The following text examines fief holding by women in the surviving charters from Saxony from about the 11th to the beginning of the 14th centuries. Specifically, these are the areas around Harz delimited by the five bishoprics of Meissen, Naumburg, Hildesheim, Halberstadt, and Merseburg. The basis for analysis is collections of charters from these dioceses supplemented by the collections of charters from the two most significant noble houses active in this area — the houses of Ascania and Welf. The selection of sources and region is not a coincidence: It is probably where Eike von Repgow lived most of his life and wrote his Saxon Mirror (Sachsenspiegel), which significantly influences the modern study of medieval law. Through an analysis of the terminology associated with fiefs and feudal institutions in general, as well as through specific examples of fief holding by women, this study attempts to show that the limitations on a woman holding a fief as defined by Eike in the Saxon Mirror and largely accepted in the contemporary literature are not entirely consistent with the testimony of these diplomatic sources. [ABSTRACT FROM AUTHOR]

The medieval perception of the foreigner and the "other" was not an isolated phenomenon, but part of a broader image of the ideological and real worlds, in which people who did not come from a different country but represented some social, cultural and other differences could be regarded as "foreign". This is not a surprising discovery, but a logical consequence of the structure of medieval society. Thus we can assume that the more "social bubbles" and hence imagined "boundaries" there are in society, the bigger the collection of people, phenomena etc. which in some circumstances may be regarded as "foreign". However, this brief reflection is not aimed at refining the definition of the "foreigner" in medieval Bohemian sources or at providing further evidence of the multifaceted nature of the concept. It focuses only on the question of whether and how the issue of the "foreigners" is reflected also in other thematic areas of modern medieval studies. Using several source examples, the author seeks to demonstrate how the phenomenon of the "foreigner" can in some circumstances be used as a kind of analytical category in seemingly distant topics. [ABSTRACT FROM AUTHOR]