| 1. |
- Ahmad, Anees, et al.
(författare)
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Oxidative rearrangement of alkenes using in situ generated hypervalent iodine(III)
- 2013
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Ingår i: Tetrahedron Letters. - : Elsevier BV. - 0040-4039 .- 1359-8562. ; 54:43, s. 5818-5820
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Tidskriftsartikel (refereegranskat)abstract
- A novel protocol for the oxidative rearrangement of alkenes using in situ generated hypervalent iodine(III) was developed. This approach uses inexpensive, readily available, and stable chemicals (PhI, mCPBA, and TsOH) giving rearrangement products in yields comparable to those obtained using the more expensive commercially available [hydroxy(tosyloxy)iodo]benzene [HTIB or Koser's reagent]. Additionally, an alternative protocol for the synthesis of 1-methyl-2-tetralone through the one-step epoxidation/rearrangement of 4-methyl-1,2-dihydronaphthalene using mCPBA and TsOH was developed.
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| 2. |
- Ghosh, Raju, et al.
(författare)
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Room Temperature, Metal-Free Arylation of Aliphatic Alcohols
- 2014
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Ingår i: ChemistryOpen. - : Wiley. - 2191-1363. ; 3:2, s. 54-57
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Tidskriftsartikel (refereegranskat)abstract
- Diaryliodonium salts are demonstrated as efficient arylating agents of aliphatic alcohols under metal-free conditions. The reaction proceeds at room temperature within 90min to give alkyl aryl ethers in good to excellent yields. Aryl groups with electron-withdrawing substituents are transferred most efficiently, and unsymmetric iodonium salts give chemoselective arylations. The methodology has been applied to the formal synthesis of butoxycaine.
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| 3. |
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| 4. |
- Jalalian, Nazli, 1982-, et al.
(författare)
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Design and asymmetric synthesis of chiral diaryliodonium salts
- 2010
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Ingår i: Tetrahedron. - : Elsevier BV. - 0040-4020 .- 1464-5416. ; 66:31, s. 5793-5800
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Tidskriftsartikel (refereegranskat)abstract
- The application of chiral hypervalent iodine reagents in asymmetric synthesis is highly desirable, as the reagents are metal-free, environmentally benign and employed under mild conditions. Three chiral diaryliodonium salts have been designed to provide chemoselectivity and asymmetric induction in asymmetric alpha-phenylation of carbonyl compounds. The synthetic routes to the selected targets are detailed herein, together with a structural investigation into the diastereoselectivity of the alkylation process.
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| 5. |
- Jalalian, Nazli, 1982-
(författare)
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Development and Applications of Hypervalent Iodine Compounds : Powerful Arylation and Oxidation Reagents
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The first part of this thesis describes the efficient synthesis of several hypervalent iodine(III) compounds. Electron-rich diaryliodonium salts have been synthesized in a one-pot procedure, employing mCPBA as the oxidant. Both symmetric and unsymmetric diaryliodonium tosylates can be isolated in high yields. An in situ anion exchange also enables the synthesis of previously unobtainable diaryliodonium triflates.A large-scale protocol for the synthesis of a derivative of Koser’s reagent, that is an isolable intermediate in the diaryliodonium tosylate synthesis, is furthermore described. The large-scale synthesis is performed in neat TFE, which can be recovered and recycled. This is very desirable from an environmental point of view.One of the few described syntheses of enantiopure diaryliodonium salts is discussed. Three different enantiopure diaryliodonium salts bearing electron-rich substituents are synthesized in moderate to high yields. The synthesis of these three salts shows the challenge in the preparation of electron-rich substituted unsymmetric salts.The second part of the thesis describes the application of both symmetric and unsymmetric diaryliodonium salts in organic synthesis. A metal-free efficient and fast method for the synthesis of diaryl ethers from diaryliodonium salts has been developed. The substrate scope is wide as both the phenol and the diaryliodonium salt can be varied. Products such as halogenated ethers, ortho-substituted ethers and bulky ethers, that are difficult to obtain with metal-catalyzed procedures, are readily prepared. The mild protocol allows arylation of racemization-prone a-amino acid derivatives without loss of enantiomeric excess.A chemoselectivity investigation was conducted, in which unsymmetric diaryliodonium salts were employed in the arylation of three different nucleophiles in order to understand the different factors that influence which aryl moiety that is transferred to the nucleophile.
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| 6. |
- Jalalian, Nazli, et al.
(författare)
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Metal-Free Arylation of Oxygen Nucleophiles with Diaryliodonium Salts
- 2012
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Ingår i: Chemistry - A European Journal. - : Wiley. - 0947-6539 .- 1521-3765. ; 18:44, s. 14140-14149
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Tidskriftsartikel (refereegranskat)abstract
- Phenols and carboxylic acids are efficiently arylated with diaryliodonium salts. The reaction conditions are mild, metal free, and avoid the use of halogenated solvents, additives, and excess reagents. The products are obtained in good-to-excellent yields after short reaction times. Steric hindrance is very well tolerated, both in the nucleophile and diaryliodonium salt. The scope includes ortho-and halo-substituted products, which are difficult to obtain by metal-catalyzed protocols. Many functional groups are tolerated, including carbonyl groups, heteroatoms, and alkenes. Unsymmetric salts can be chemoselectively utilized to obtain products with hitherto unreported levels of steric congestion. The arylation has been extended to sulfonic acids, which can be converted to sulfonate esters by two different approaches. With recent advances in efficient synthetic procedures for diaryliodonium salts the reagents are now inexpensive and readily available. The iodoarene byproduct formed from the iodonium reagent can be recovered quantitatively and used to regenerate the diaryliodonium salt, which improves the atom economy.
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| 7. |
- Jalalian, Nazli, et al.
(författare)
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Room temperature, metal-free synthesis of diaryl ethers with use of diaryliodonium salts
- 2011
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Ingår i: Abstracts of Papers, 242nd ACS National Meeting & Exposition, Denver, CO, United States, August 28-September 1, 2011. - : American Chemical Society.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Diaryl ethers are common structural features in numerous natural products and biol. active compds. Despite more than a century of immense focus on finding efficient synthetic routes to this compd. class, diaryl ethers remain difficult to obtain. Routes that are catalytic in copper have been developed, but high catalyst loadings, excess reagents, elevated temps. and long reaction times are still needed. Pd-catalyzed cross-couplings of phenols and aryl halides at temps. up to 100 °C have recently been reported to give high yields of diaryl ethers. Diaryliodonium salts are non-toxic alternatives to transition metals in the synthesis of diaryl ethers and we have recently developed effective synthetic routes to these salts. Herein we report a fast, high-yielding synthesis of diaryl ethers. The reaction conditions are mild, metal-free, and avoid the use of halogenated solvents, additives, or excess reagents. Precautions to avoid air or moisture are not needed. The scope includes ortho- and halo-substituted diaryl ethers, which are difficult to obtain by metal-catalyzed protocols .
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| 8. |
- Jalalian, Nazli, 1982-, et al.
(författare)
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Room temperature, metal-free synthesis of diaryl ethers with use of diaryliodonium salts
- 2011
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Ingår i: Organic Letters. - : American Chemical Society (ACS). - 1523-7060 .- 1523-7052. ; 13:6, s. 1552-1555
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Tidskriftsartikel (refereegranskat)abstract
- A fast, high-yielding synthesis of diaryl ethers with use of mild and metal-free conditions has been developed. The scope includes bulky orthosubstituteddiaryl ethers, which are difficult to obtain by metal-catalyzed protocols. Halo-substituents, racemization-prone amino acid derivatives,and heteroaromatics are also tolerated. The methodology is expected to be of high utility in the synthesis of complex molecules and in thepharmaceutical industry.
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