Remote functionalization of alkenes via chain walking has generally been limited to C(sp
)-H bonds α and β to polar-functional units, while γ-C(sp
)-H functionalization through controlled alkene ...transposition is a longstanding challenge. Herein, we describe NiH-catalyzed migratory formal hydroamination of alkenyl amides achieved via chelation-assisted control, whereby various amino groups are installed at the γ-position of aliphatic chains. By tuning olefin isomerization and migratory hydroamination through ligand and directing group optimization, γ-selective amination can be achieved via stabilization of a 6-membered nickellacycle by an 8-aminoquinoline directing group and subsequent interception by an aminating reagent. A range of amines can be installed at the γ-C(sp
)-H bond of unactivated alkenes with varying alkyl chain lengths, enabling late-stage access to value-added γ-aminated products. Moreover, by employing picolinamide-coupled alkene substrates, this approach is further extended to δ-selective amination. The chain-walking mechanism and pathway selectivity are investigated by experimental and computational methods.
Reported herein is a modular, NiH-catalyzed system capable of proximal-selective hydroamination of unactivated alkenes with diverse amine sources. The key to the successful implementation of this ...approach is the promotion of NiH insertion into even highly substituted olefins via coordination of the bidentate directing group to the nickel complex. A wide range of primary and secondary amines can be installed in both internal and terminal unactivated alkenes with excellent regiocontrol under the optimized reaction conditions. This protocol is flexible and general for the preparation of a variety of valuable β- and γ-amino acid building blocks that would otherwise be difficult to synthesize. The utility of this transformation was further demonstrated by the site-selective late-stage modification of complex and medicinally relevant molecules. Combined experimental and computational studies illuminate the detailed reaction mechanism.
Chelation‐assisted C−H bond and alkene functionalization using bidentate directing groups offers an elegant and versatile approach to overcome regiocontrol issues by allowing the catalyst to come ...into close proximity with the targeted sites. In this personal account, we highlight our recent works in developing regio‐ and stereocontrolled functionalizations through transition‐metal catalysis enabled by bidentate directing groups. We classify our results into two categories: (1) regioselective alkene functionalization using bidentate directing groups, and (2) asymmetric C–H functionalization using chiral bidentate directing groups. Furthermore, density functional theory studies to elucidate the origin of the regio‐ and stereoselectivity exerted by bidentate directing groups are discussed.
This personal account focuses on the recent development of regioselective alkene functionalization through transition‐metal catalysis enabled by bidentate directing groups. Asymmetric C−H functionalization using chiral bidentate directing groups is also highlighted.
Purpose
This study aims to systematise the methodology used in comparative urban planning law and propose primary contexts for comparison in planning law.
Design/methodology/approach
This study ...undertook a review of comparative law methodology discourse and sought to establish connections between the discourse and the field of planning law.
Findings
This study argues for establishment of a realistic goal for comparative planning law by focusing on the planning law's modifiability. The goal of comparison in planning law should not be to find universally desirable principles or better solutions. Rather, the goal should be to identify a motive for devising a solution. This is because it is not only difficult to establish legal values that are universally applicable to planning law but also inappropriate to determine superiority of planning laws that have been developed over time by each jurisdiction’s sovereignty and policies on land use. When determining comparable systems for analysis among legal systems that are functionally equivalent, it is important to consider the context of land use relations alongside the comparative analysis to be done. To set realistic goals, the context should not be extended indefinitely but be systematised. Based on the foundational relationship underlying planning law, including the tension between planning authorities and property owners, this study presents five specific contexts for comparative analysis: “Strength of Property Rights,” “Level of Judicial Intervention,” “Plan- or Development-led System,” “Allocation of Planning Power” and “Level of Participation.” Examination of these contexts will allow better understanding of the similarities and differences among different systems and practical application of the results of comparative studies.
Originality/value
This study presents a novel approach to systematising the methodology and framework of comparative planning law.
A palladium(II)-catalyzed 1,1-difunctionalization of unactivated terminal and internal alkenes via addition of two nucleophiles was developed using a cationic palladium(II) complex. The ...palladacycle generated in situ as a result of a regioselective addition of a nucleophile to the alkene can readily undergo regioselective β-hydride elimination and migratory insertion with a cationic palladium catalyst. The resulting η3-π-allyl palladium(II) complex is the key intermediate that reacts with a second nucleophile to furnish the desired 1,1-difunctionalization of the alkene. Under the optimized reaction conditions, a wide range of indoles and anilines add to alkene units of 3-butenoic or 4-pentenoic acid derivatives to afford the synthetically useful γ,γ- or δ,δ-difunctionalized products with excellent regiocontrol. Furthermore, by employing internal hydroxyl or acid groups and external carbon nucleophiles, this transformation enables unsymmetric 1,1-difunctionalization to forge challenging and important oxo quaternary carbon centers. Combining experiments and DFT calculations on the mechanism of the reaction is investigated in detail.
The photocatalyzed ortho‐selective migration on a pyridyl ring has been achieved for the site‐selective trifluoromethylative pyridylation of unactivated alkenes. The overall process is initiated by ...the selective addition of a CF3 radical to the alkene to provide a nucleophilic alkyl radical intermediate, which enables an intramolecular endo addition exclusively to the ortho‐position of the pyridinium salt. Both secondary and tertiary alkyl radicals are well‐suited for addition to the C2‐position of pyridinium salts to ultimately provide synthetically valuable C2‐fluoroalkyl functionalized pyridines. Moreover, the method was successfully applied to the reaction with P‐centered radicals. The utility of this transformation was further demonstrated by the late‐stage functionalization of complex bioactive molecules.
Remote migration: The photocatalyzed ortho‐selective migration on a pyridyl ring has been achieved for the site‐selective trifluoromethylative pyridylation of unactivated alkenes under mild reaction conditions. Notably, this method could be successfully extended to tertiary radicals to forge quaternary C centers bearing C2‐substituted pyridyl groups, overriding the commonly observed preference for the C4 addition.
The photocatalyzed ortho‐selective migration on a pyridyl ring has been achieved for the site‐selective trifluoromethylative pyridylation of unactivated alkenes. The overall process is initiated by ...the selective addition of a CF3 radical to the alkene to provide a nucleophilic alkyl radical intermediate, which enables an intramolecular endo addition exclusively to the ortho‐position of the pyridinium salt. Both secondary and tertiary alkyl radicals are well‐suited for addition to the C2‐position of pyridinium salts to ultimately provide synthetically valuable C2‐fluoroalkyl functionalized pyridines. Moreover, the method was successfully applied to the reaction with P‐centered radicals. The utility of this transformation was further demonstrated by the late‐stage functionalization of complex bioactive molecules.
Die photokatalytische ortho‐selektive Migration an einem Pyridylring ermöglicht eine regioselektive trifluormethylierende Pyridylierung von nicht‐aktivierten Alkenen unter milden Reaktionsbedingungen. Die Methode konnte auf tertiäre Radikale ausgedehnt werden, um quartäre C‐Zentren mit C2‐substituierten Pyridylgruppen zu erzeugen, was die häufig beobachtete Präferenz für die C4‐Addition überlagert.
정비사업, 그중에서도 재개발사업의 경우 정비구역 내에 종교시설과 같은 상대적으로 넓은 규모의 부지가 포함되어 있는 경우가 발견된다. 이 경우 종교시설의 특성상 정비사업에 참여하는 조합원의 하나로 보아 공동주택이나 상가를 분배하거나, 혹은 수용의 대상으로 삼아 단순히 현금보상의 대상으로 삼는 것 모두가 부적절해 보일 수 있고, 실무적으로도 상당한 민원을 ...촉발하게 될 가능성이 존재한다. 때문에 서울시는 2009년 이래 종교시설을 되도록 현 위치 그대로 존치하도록 하되, 이전이 불가피한 경우에는 그와 거의 유사한 규모로 이전하여주도록 하는 내용의 방침을 수립하여 적용해왔는데, 후자의 경우 실무상 ‘대토’ 혹은 ‘대토합의’라는 명칭이나 형태로 체결되어왔다.
문제는 이와 같은 대토 혹은 대토합의라는 것이 도시정비법상 명확한 근거를 찾기 어렵다는 점에 있다. 급기야 최근에 들어서는 대토를 받은 종교단체에 대하여 사업시행자인 조합이 청산금을 부과하여 사업비를 분담시키려는 분쟁사례도 발견되는데, 이는 근본적으로 대토의 법적 성격을 어떻게 규명할 것인지가 선행적으로 검토되어야만 해결이 가능한 쟁점이 된다. 도시정비법 및 토지보상법상 대토와 외형상 유사한 개념으로는 ‘환지’나 ‘대토보상’이라는 것이 존재하는데, 대토가 어느 것에 가까운지에 따라 대토를 받는 자의 법적 지위가 정비사업에 참여하는 조합원의 지위에 놓여있는 것인지, 아니면 정비사업에서 제외, 배제되면서 보상을 받게 되는 지위에 놓여있는 것인지가 결정되기 때문이다.
이에 본고에서는 ① 정비사업의 시행방식이나 추진과정, 조합원 지위의 의미 등을 분석함으로써 정비사업에서 대토가 등장하게 되는 배경을 설명하고, ② 이를 토대로 정비사업에서의 대토의 법적 성격을 어떻게 규명하여야 할 것인지에 대하여 고찰하여 보고자 한다. 아울러, ③ 정비사업에서 나타나는 대토의 유형이나 형태가 다변화되어 있는 만큼, 각각의 경우에 대두될 수 있는 법적 문제를 짚어봄으로써, 이것이 대토 및 대토합의의 효력에 어떠한 영향을 미치게 되는 것인지에 대하여도 고찰하여보도록 한다. 이를 통해 정비사업 실무상 등장하고 있는 대토를 둘러싼 법률관계와 쟁점을 명확히 함으로써, 추후 등장할 수 있는 대토에 관한 분쟁에서 그 해결을 위한 단초나 논의되어야 할 쟁점의 구조를 규명해보고자 한다. In the case of improvement projects, especially redevelopment projects, a case where a relatively large site such as a religious facility is included in the improvement zone is discovered. In this case, due to the characteristics of the religious facilities, it is inappropriate to distribute the apartment or office building, just as one of the members(land owners) participating in the improvement project. Or it is also inappropriate to simply compensate as cash rewards when they deny to participate in the project. In practice, there is also a possibility of considerable complaints by religious facilities. Therefore, in 2009, Seoul metropolitan city government made a policy that in improvement zone a religious facility shall maintain its current location, but if it is unavoidable, it will be moved as almost the same scale by expense of implementer(developer). In the latter case, it has been concluded with the name and form of “land provision” or “land provision agreement” in practice.
The problem is that such “land provision” or “land provision agreement” is difficult to find a clear basis for the ‘ACT ON THE IMPROVEMENT OF URBAN AREAS AND RESIDENTIAL ENVIRONMENTS’(Urban Improvement Act). Recently, a case of a dispute has been discovered in which project implementer(developer) imposes cost of improvement project on a religious organization. Fundamentally this case is about whether land owner who get land provision is one of participant in the improvement project and it is also about legal character of “land provision” or “land provision agreement”. Urban Improvement Act and Land Compensation Act has similar concept such as “Replotting” or “Compensation of Substitution Land”, and which legal concept can explain better the meaning of “land provision” is related to the legal status of those who receive “land provision”.
In this paper, (1) by analyzing the method and process of the improvement project, the meaning of the status of the land owner or participant in the project, we analyzed the background of the appearance of “land provision” in the improvement project, and (2) based on this, this paper will investigate the legal character of “land provison”. After then, this paper will explore legal issues regarding to validity of “land provision”. KCI Citation Count: 0
PDF
