One-Pot Synthesis of Rotationally Restricted, Conjugatable, BODIPY Derivatives from Phthalides

Abstract

O-Ethylation of phthalides with Meerwein's reagent followed by reaction of the ensuing salts with pyrrole, results in the formation of 5-alkoxy-5-phenyl dipyrromethane derivatives, which function as ready precursors of ortho-substituted 8-aryl BODIPY derivatives by reaction with borontrifluoride etherate, an overall process that can be carried out in a one-pot operation.

Solvent‐Sensitive Emitting Urea‐Bridged bis‐BODIPYs: Ready Access by a One‐Pot Tandem Staudinger/Aza‐Wittig Ureation

“…[30] Access to BODIPYs 8b,w as initially carried out by an efficient Liebeskind-Srçgl cross-coupling reaction, [31] as described by PeÇa-Cabrera's group. [34] In this manuscript, we describe the synthesis and computationally aided photophysical properties of urea-bridged bis-BODIPYs 9,w hich are available by ao ne-step reaction of BODIPY azides, 8b,v ide infra ( Figure 2). [34] In this manuscript, we describe the synthesis and computationally aided photophysical properties of urea-bridged bis-BODIPYs 9,w hich are available by ao ne-step reaction of BODIPY azides, 8b,v ide infra ( Figure 2).…”

“…[38,39] Results and Discussion Synthesis As previously mentioned, our interest in the preparation of conjugatable BODIPYs had led us to the preparation of several BODIPY derivatives (including formyl and isothiocyanyl derivatives). [34] In this context, to gain access to BODIPY-amines, we attempted the well-known Staudinger "azido!amino" transformation (PPh 3 ,a q. NaOH), [40] from BODIPY-azide, 10 (Scheme 1). However,S taudinger reduction of 10 did not led to the desired BODIPY amine 11,a nd instead, bridged-urea bis-BODIPY 12 could be isolated in fairly good yields (Scheme 1).…”

Towards Efficient and Photostable Red‐Emitting Photonic Materials Based on Symmetric All‐BODIPY‐Triads, ‐Pentads, and ‐Hexads

“…BODIPY monomers 11, 12, 13, 14, 15 b, 17 and 18 were prepared according to previously reported methods. [26] General procedures General method for Knoevenagel reaction. a) At 80 8 8Cu nder microwave (MW) irradiation:T oasolution of the corresponding BODIPY 14-16 (0.1 mmol) and the aromatic aldehyde (4 equiv) in dry DMF (25 mL mmol À1 )w ere added piperidine (0.1 mL) and acetic acid (0.1 mL).…”

“…As previously mentioned, our approacht om ultichromophores 6-10,s tarted from as ingle precursor,8 -phenyl ortho-hydroxymethyl BODIPY 11,r eadily available by ao ne-pot protocol previously described in our laboratory. [26] In this context,s ynthetic transformations on the hydroxymethyl moiety of 11 paved the way to azidomethyl and formyl BODIPYs 12 and 13,respectively. [26] Subsequent synthetic post-modifications on the dipyrromethenec ore of 11 allowed access to differently2 ,6-disubstituted derivatives 14, [26] 15 a, 15 b [26] and 16 (Figure 3).…”

“…[26] In this context,s ynthetic transformations on the hydroxymethyl moiety of 11 paved the way to azidomethyl and formyl BODIPYs 12 and 13,respectively. [26] Subsequent synthetic post-modifications on the dipyrromethenec ore of 11 allowed access to differently2 ,6-disubstituted derivatives 14, [26] 15 a, 15 b [26] and 16 (Figure 3). Compounds 15 and 16,w ith p-extended conjugation, displayed red-shifted absorption and emission in agreement with literature precedents.…”