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Updated: May 1, 2026
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Synthesis and structure of a 1-phospha-2-boraacenaphthene derivative and its chalcogenation reactions
Abstract:
The first stable 1-phospha-2-boraacenaphthene 1 was synthesized by the reduction of 1-dimesitylboryl-8-dichlorophosphinonaphthalene (2a) with elemental magnesium, and it was fully characterized. The chalcogenation reaction of 1 with elemental sulfur or selenium afforded the unique heterocycles, 2-thia- and 2-selena-1-phospha-3-boraphenalenes 9S and 9Se, respectively, through the insertion of the chalcogen atom into a P-B bond of 1. Further chalcogenation of 9 afforded the corresponding phosphine chalcogenides. These newly obtained chalcogenated compounds have been characterized. The unique dynamic behavior of 2-chalcogena-1-phospha-3-boraphenalene-1-chalcogenides 10 in solution has also been described.
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