The properties of nanographenes can be tuned by changing their shapes, therefore the development of new methods suitable for the synthesis of various nanographenes is highly desirable. Described herein is an intramolecular InCl3/AgNTf2‐catalyzed regioselective domino benzannulation reaction of buta‐1,3‐diynes to build irregular nanographenes. Different nanographene compounds were easily obtained in moderate to high yields through careful design of the precursor compounds. This new domino reaction was successfully applied to a fourfold alkyne benzannulation of dimethoxy‐1,1′‐binaphthalene derivatives to arrive at novel chiral butterfly ligand precursors. The regioselectivity of the benzannulation reaction was unambiguously confirmed by X‐ray crystallography. Moreover, this new method enables us to synthesize different nanographene isomers and study their optical properties as a function of shape.
We report a transition metal‐free, regio‐ and stereo‐selective, phosphine‐catalyzed method for the
- NSF-PAR ID:
- 10370606
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 28
- Issue:
- 63
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The properties of nanographenes can be tuned by changing their shapes, therefore the development of new methods suitable for the synthesis of various nanographenes is highly desirable. Described herein is an intramolecular InCl3/AgNTf2‐catalyzed regioselective domino benzannulation reaction of buta‐1,3‐diynes to build irregular nanographenes. Different nanographene compounds were easily obtained in moderate to high yields through careful design of the precursor compounds. This new domino reaction was successfully applied to a fourfold alkyne benzannulation of dimethoxy‐1,1′‐binaphthalene derivatives to arrive at novel chiral butterfly ligand precursors. The regioselectivity of the benzannulation reaction was unambiguously confirmed by X‐ray crystallography. Moreover, this new method enables us to synthesize different nanographene isomers and study their optical properties as a function of shape.
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Abstract The 1,4‐diacyloxylation of 1,3‐cyclohexadiene (CHD) affords valuable stereochemically defined scaffolds for natural product and pharmaceutical synthesis. Existing
cis ‐selective diacyloxylation protocols require superstoichiometric quantities of benzoquinone (BQ) or MnO2, which limit process sustainability and large‐scale application. In this report, reaction development and mechanistic studies are described that overcome these limitations by pairing catalytic BQ withtert ‐butyl hydroperoxide as the stoichiometric oxidant. Catalytic quantities of bromide enable a switch fromtrans tocis diastereoselectivity. A catalyst with a 1:2 Pd:Br ratio supports highcis selectivity while retaining good rate and product yield. Further studies enable replacement of BQ with hydroquinone (HQ) as a source of cocatalyst, avoiding the handling of volatile and toxic BQ in large‐scale applications.
