Bimane Acetylenes and Diacetylenes. Bimanes. 33

Abstract

Two series (4,6-dihydro and 4,6-dimethyl) of syn-bimanes [1,5-diazabicyclo[3.3.0]octa-3,6-diene-2,8-diones] have been converted to acetylene and diacetylene derivatives. Their chemical and photophysical properties are reported. The 3-(and 6-)iodo (diiodo) derivatives are the best choices for Stille or Heck condensations with acetylenes or acrylates. Desilylation of (trimethylsilyl)acetylenes is best carried out with silver nitrate followed by lithium bromide. The acetylenes and diacetylenes are quite stable and highly fluorescent and represent candidate units for incorporation into polymers.

1‐(Phenylethynyl)pyrene and 9,10‐Bis(phenylethynyl)anthracene, Useful Fluorescent Dyes for DNA Labeling: Excimer Formation and Energy Transfer

“…[3] The introduction of the phenylethynyl group into a fluorescent molecule usually leads to a bathochromic shift in absorbance and emission, as well as an increase in the quantum yield of emission. This has been shown for naphthalene, [15] anthracene and tetracene, [16] pyrene, [17] perylene, [18] 2-phenylbenzoxazole, [19] bimanes, [20] Eu III chelates, [21] coumarins, [22] BODIPY, [23] and fluorescein. [24] Suitably functionalized phenylethynyl derivatives of pyrene and anthracene could be promising tools for the development of fluorescent probes for structural studies of nucleic acids.…”

Bivalent glycoconjugates based on 1,5-diazabicyclo[3.3.0]octa-3,6-diene-2,8-dione (“bimane”) as a central scaffold

“…As a further option to attach glycosyl moieties to the bimane skeleton we have explored approaches by taking advantage of the Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC, "click" ) reaction (for a review of applications in carbohydrate chemistry, see reference [38]) for this purpose. We have selected the bimane diacetylene derivative 1h [39] for reactions with glycosyl azides 12a,b,c,d under "click" conditions and, to our satisfaction, 3,7-disubstituted bimane triazole derivatives 13a,b,c,d could be obtained in moderate to good yields (Scheme 4 and Table 1). (Figure S1) as well as for details of structure determination and refinement see Supplementary Information (Table S1).…”

A dipodal bimane–ditriazole–diCu(ii) complex serves as an ultrasensitive water sensor

“…The precursor was synthesized following literature-reported procedures (see ESI † for more details). 15 This compound, which displays an impressive molar extinction coefficient (e = 1.32 Â 10 4 L mol À1 Ácm À1 ) and high quantum yield (relative j = 0.98 in anh. acetonitrile), forms a dipodal complex with copper(II) cations, which is nearly non-fluorescent due to metalinduced fluorescence quenching.…”

“…In principle, the formation of metal complexes such as the complex between compound 1 and copper(II) can be followed by NMR by measuring changes in chemical shifts and/or peak broadening. In our system, full assignments of compound 1 and its copper complex were achieved by using onedimensional 1 H NMR and two-dimensional 1 H/ 13 C (HMQC and HMBC) and 1 H/ 15 N HMBC NMR (for detailed analysis see ESI †).…”