1794-48-5Relevant articles and documents
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Lappin
, p. 3966 (1949)
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Copper(I)-Catalyzed Intramolecular Cyclization of o-Propargyloxy Diketopiperazines to Access Diverse Diazabicyclic and Spiro-Diketopiperazinochromanes
Armaghan, Mahsa,Balalaie, Saeed,Bijanzadeh, Hamid Reza,Frank, Walter,Manavi, Bita,Rominger, Frank,Tejeneki, Hossein Zahedian
supporting information, p. 4190 - 4196 (2021/08/06)
In this report, two distinctive intramolecular cyclizations of o-propargyloxy diketopiperazines (achieved from a one-pot Ugi post-transformation) is achieved via a copper(I)-catalyzed intramolecular reaction of azomethine ylide and alkyne moiety. The presence of internal alkyne in the starting materials directed the reaction towards through [3+2]-cycloaddition, while terminal alkyne led to a spirocyclization reaction between azomethine ylide and terminal unsaturated C?C bond. This method offering an opportunity for the synthesis of challenging Diazabicyclics and Spiro-Diketopiperazinochromanes in high yields with exclusive diastereoselectivity. (Figure presented.).
Iron-Catalyzed [2+2+2] Annulation of Aliphatic Bridged 1,n-Enynes with Aldehydes for the Synthesis of Fused Pyrans
Tian, Tian,Wang, Xin,Lv, Leiyang,Li, Zhiping
supporting information, p. 4425 - 4428 (2020/06/05)
An iron-catalyzed [2+2+2] annulation of aliphatic bridged 1,n-enynes with aldehydes was developed. Aldehydes play a dual role as the precursors of acyl radicals to trigger the cascade cyclization but also as the radical acceptors to terminate the annulation. This two-in-one strategy overcomes the limitation in [2+2+m] cyclization that requires a rigid benzene skeleton as the essential linker, thus enabling the efficient synthesis of functionalized fused [5.6] and [6.6] pyran skeletons.
Regioselective Iron-Catalysed Cross-Coupling Reaction of Aryl Propargylic Bromides and Aryl Grignard Reagents
Manjón-Mata, Inés,Quirós, M. Teresa,Bu?uel, Elena,Cárdenas, Diego J.
supporting information, p. 146 - 151 (2019/12/11)
An iron-catalysed Kumada-type cross-coupling reaction between aryl substituted propargylic bromides and arylmagnesium reagents has been developed. Propargylic coupling products were the main or only outcome, and propargyl/allene regioselectivity was shown to depend on the electronic nature of the substituents on the triple bond of the substrate and on the arylmagnesium halide. Best selectivities were observed when electron donating substituents were present in either reagent. The process is stereoespecific, occurs with configuration inversion and no carbon-based radicals seem to be involved in the mechanism. (Figure presented.).
