Rearrangements and reductive cleavage of 3a,6a-diaza-1,4-diphosphapentalenes

Abstract

The interaction of 1,4-dichloro-3а,6а-diaza-1,4-diphosphapentalenes with metallic Na, Li, or naphthalene-Na anion-radical salt in THF proceeds through several successive stages: dehalogenation, two types of rearrangement of the heteropentalene fragment to form...

Hemetsberger–Knittel and Ketcham Synthesis of Heteropentalenes with Two (1:1), Three (1:2)/(2:1) and Four (2:2) Heteroatoms

“…With respect to our research aims [15,16], together with taking into account the enor mous number of existing derivatives, herein we have highlighted the synthesis of fur [3,2-b]pyrroles (V, Figure 3) using a three-step Hemetsberger-Knittel procedure, and thi azolo [5,4-d]thiazoles (VI, Figure 3) as representative products of the Ketcham reaction While the furo [3,2-b]pyrroles come from a category of O,N-two heteroatoms containing HPs with applications in pharmaceuticals, the thiazolo [5,4-d]thiazole scaffold consists o two thiazole rings containing a combination of four heteroatoms, nitrogen and sulphur in each annelated core and are very important in applied science for the development o optoelectronic devices such as organic photovoltaic cells (OPV and organic field-effec transistors (OFETs). but a few reports on HPs with phosphorus [8], boron [9] or silicon [10] in the position of heteroatom have recently been published.…”

“…Reactions 2023, 4 255 but a few reports on HPs with phosphorus [8], boron [9] or silicon [10] in the position of heteroatom have recently been published.…”

“…Reactions 2023, 4, FOR PEER REVIEW altogether, including the non-classical heteropentalenes and betaines, the number of pos sible isoconjugates has reached an uncountable number. Generally, oxygen, sulphur, ni trogen, selenium and tellurium are the most commonly employed as heteroatoms [1][2][3][4][5][6][7] but a few reports on HPs with phosphorus [8], boron [9] or silicon [10] in the position o heteroatom have recently been published. For a structural description in combination with the HPs' nomenclature, the genera formula (1) can be applied for recognising the appropriate hetarene [11] according to:…”

A New Class of Two‐Deck Dicationic Heteropentalenes Existing by the Balance between Interdeck Aromaticity and Covalent P−P Bonding

“…The chemical properties of 3a,6a‐diaza‐1,4‐diphosphapentalene can be quite clearly divided into two types. The first type includes reactions of the heterocyclic system (formation of π‐complexes with organic π‐acceptors, [18] cycloaddition reactions, [21] rearrangement of DDP framework [22] ). The second type are reactions of stabilized singlet phosphinidene (oligomerization, [20] complexation with metal salts and Lewis acids, [23,24] oxidative addition reactions, [25–28] formation of adducts with carbenes [29,30] …”