06/02/2023 - Indole Building Blocks

Aslan, Murat et al. published their research in Journal of Organic Chemistry in 2022 | CAS: 320734-35-8

7-Bromooxindole (cas: 320734-35-8) belongs to indole derivatives. Indole, first isolated in 1866, and it is commonly synthesized from phenylhydrazine and pyruvic acid, although several other procedures have been discovered.Indole was synthesized in moderate yield via an o-naphthoquinone catalyzed tandem cross-coupling of substituted aniline and benzylamine under aerobic oxidation conditions.COA of Formula: C8H6BrNO

Functionalization at Nonperipheral Positions of Triazatruxene: Modular Construction of 1,6,11-Triarylated-Triazatruxenes for Potentially Organic Electronics and Optoelectronics was written by Aslan, Murat;Taskesenligil, Yunus;Pravadl, Selin;Saracoglu, Nurullah. And the article was included in Journal of Organic Chemistry in 2022.COA of Formula: C8H6BrNO This article mentions the following:

Functionalization from nonperipheral positions of triazatruxene is representing a challenge. Triarylation of the nonperipheral positions (1, 6, and 11) in triazatruxene scaffold has been achieved for the first time via two approaches. The transformations involve arylation/cyclotrimerization and cyclotrimerization/arylation sequences. POCl3-mediated direct cyclotrimerization of oxindoles containing electron-deficient substituents on the aryl group at the C7-position resulted in the formation of 2-chloroindoles, whereas oxindoles containing electron-donating substituents gave the triazatruxenes. Furthermore, desired triazatruxenes were achieved through cyclotrimerization of 7-bromooxindole followed by coupling with arylboronic acids. As a representative triazatruxene scaffold, the optoelectronic properties of I have also been studied via UV-visible (UV-vis) absorption spectra and fluorescence spectra of I thin films. Also, d. functional theory calculation was realized to get knowledge about frontier MOs. In the light of the information obtained, an organic light-emitting diode (OLED) device utilizing I as an emissive layer was applied to obtain white emission. In brief, this study provides the first examples of the synthesis of triazatruxenes bearing aryl substituents at the nonperipheral positions as candidate compounds for organic electronics, optoelectronics, and material chem. In the experiment, the researchers used many compounds, for example, 7-Bromooxindole (cas: 320734-35-8COA of Formula: C8H6BrNO).

Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles

Ma, Bingqing et al. published their research in Journal of Fluorine Chemistry in 2015 | CAS: 4769-96-4

6-Nitro-1H-indole (cas: 4769-96-4) belongs to indole derivatives. Indole could be stereoselectively alkylated with chiral cyclopentyl sulfone reagent. It is used in perfumery and in making tryptophan, an essential amino acid, and indoleacetic acid (heteroauxin), a hormone that promotes the development of roots in plant cuttings.Name: 6-Nitro-1H-indole

BrOsted acid-catalyzed electrophilic trifluoromethylthiolation of indoles using thermally stable trifluoromethylthiolating reagent was written by Ma, Bingqing;Shao, Xinxin;Shen, Qilong. And the article was included in Journal of Fluorine Chemistry in 2015.Name: 6-Nitro-1H-indole This article mentions the following:

A BrOsted acid-catalyzed electrophilic trifluoromethylthiolation of indoles under mild conditions is described. The reaction was insensitive to moisture and oxygen, that should allow for easy handling. In addition, the reaction is compatible with a variety of functional groups. In the experiment, the researchers used many compounds, for example, 6-Nitro-1H-indole (cas: 4769-96-4Name: 6-Nitro-1H-indole).

Ma, Zhenhui et al. published their research in Nano Research in 2019 | CAS: 4769-96-4

6-Nitro-1H-indole (cas: 4769-96-4) belongs to indole derivatives. The indole subunit is an almost ubiquitous component of biologically active natural products, and its study has been the focus of research for decades. Indole plays a fundamental role for QS in E. coli, being one of the signal molecules responsible for the transcription of a variety of genes (gabT, and tnaB ASTD). Electric Literature of C8H6N2O2

Magnetically recyclable Sm₂Co₁₇/Cu catalyst to chemoselectively reduce the 3-nitrostyrene into 3-vinylaniline under room temperature was written by Ma, Zhenhui;Liu, Hu;Yue, Ming. And the article was included in Nano Research in 2019.Electric Literature of C8H6N2O2 This article mentions the following:

Using non-noble metal catalysts to chemoselectively reduce the 3-nitrostyrene into 3-vinylaniline is extremely attractive due to the important applications of aromatic amines. However, the separation and recycle of catalytic particles to sustainably catalyze are still challenging on account of their small size. In this communication, we report a novel magnetically recyclable catalyst of Sm₂Co₁₇/Cu to chemoselectively reduce 3-nitrostyrene into 3-vinylaniline by activating ammonia borane (AB) to yield hydrogen. The Sm₂Co₁₇, composited of 180 nm Sm₂Co₁₇ nanomagnet and 10 nm Cu catalyst nanoparticles, shows a high conversion (98%) and a high selectivity (99%) for 3-nitrostyrene under ultrasonic concussion. More importantly, they are easily collected by self-separation method without any magnetic field. As a consequence, the excellent recyclable feature is acquired even underwent 10 cycles. Our approach provides a green strategy to synthesize magnetically recyclable catalysts. In the experiment, the researchers used many compounds, for example, 6-Nitro-1H-indole (cas: 4769-96-4Electric Literature of C8H6N2O2).

Walter, Antje et al. published their research in International Journal of Molecular Sciences in 2020 | CAS: 1912-45-4

2-(5-Chloro-1H-indol-3-yl)acetic acid (cas: 1912-45-4) belongs to indole derivatives. Indole, also called Benzopyrrole, a heterocyclic organic compound occurring in some flower oils, such as jasmine and orange blossom, in coal tar, and in fecal matter.Indole was synthesized in moderate yield via an o-naphthoquinone catalyzed tandem cross-coupling of substituted aniline and benzylamine under aerobic oxidation conditions.Electric Literature of C10H8ClNO2

Chlorinated auxins-how does Arabidopsis Thaliana deal with them was written by Walter, Antje;Caputi, Lorenzo;O’connor, Sarah;Van Pee, Karl-Heinz;Ludwig-Muelle, Jutta. And the article was included in International Journal of Molecular Sciences in 2020.Electric Literature of C10H8ClNO2 This article mentions the following:

Plant hormones have various functions in plants and play crucial roles in all developmental and differentiation stages. Auxins constitute one of the most important groups with the major representative indole-3-acetic acid (IAA). A halogenated derivate of IAA, 4-chloro-indole-3-acetic acid (4-Cl-IAA), has previously been identified in Pisum sativum and other legumes. While the enzymes responsible for the halogenation of compounds in bacteria and fungi are well studied, the metabolic pathways leading to the production of 4-Cl-IAA in plants, especially the halogenating reaction, are still unknown. The type of chlorinated indole derivatives that could be expected was determined by incubating wild type A. thaliana with different Cl-tryptophan derivatives We showed that, in addition to chlorinated IAA, chlorinated IAA conjugates were synthesized. Concomitantly, we found that an auxin conjugate synthetase (GH3.3 protein) from A. thaliana was able to convert chlorinated IAAs to amino acid conjugates in vitro. In addition, we showed that the production of halogenated tryptophan (Trp), indole-3-acetonitrile (IAN) and IAA is possible in transgenic A. thaliana in planta with the help of the bacterial halogenating enzymes. Furthermore, it was investigated if there is an effect (i) of exogenously applied Cl-IAA and Cl-Trp and (ii) of endogenously chlorinated substances on the growth phenotype of the plants. In the experiment, the researchers used many compounds, for example, 2-(5-Chloro-1H-indol-3-yl)acetic acid (cas: 1912-45-4Electric Literature of C10H8ClNO2).

Terent’ev, A. P. et al. published their research in Zhurnal Obshchei Khimii in 1959 | CAS: 3484-23-9

2-Methyl-6-nitro-1H-indole (cas: 3484-23-9) belongs to indole derivatives. Indole, first isolated in 1866, and it is commonly synthesized from phenylhydrazine and pyruvic acid, although several other procedures have been discovered. They are capable of binding to a variety of receptors with high affinity and thus have applications in a wide range of therapeutic areas.SDS of cas: 3484-23-9

Introduction of substituents into the benzene ring of indole. IV. Preparation of bromo-, nitro-, and aminoindoles and indolines was written by Terent’ev, A. P.;Preobrazhenskaya, M. N.;Bobkov, A. S.;Sorokina, G. M.. And the article was included in Zhurnal Obshchei Khimii in 1959.SDS of cas: 3484-23-9 This article mentions the following:

To 100 ml. concentrated H₂SO₄ was added dropwise at 5° 11.9 g. indoline, followed by 4.4 ml. HNO₃ (d. 1.5) in 100 ml. concentrated H₂SO₄ added at below 0°; after 1 hr. the mixture was quenched on ice to yield 100% 6-nitroindoline (I), m. 66.5-7.5° (ligroine); refluxing with Ac₂O gave the 1-Ac derivative, m. 154.5-5.0°. Refluxing 6.1 g. I and 9.1 g. chloranil in 300 ml. xylene 5 hrs. gave after treatment with aqueous NaOH 82% 6-nitroindole (II), m. 141-2°. Similarly, 6-nitro-2-methylindoline gave 81% 6-nitro-2-methylindole (III), m. 113.5-14.5°. Heating 1.3 g. II in 100 AcOH with 1.5 g. CrO₃ in 10 ml. H₂O 0.5 hr. on a steam bath gave 45% 6-nitroisatin, decomposing 300°; phenylhydrazone decomposed 265-6°. Similarly, III was oxidized in 1 hr. to 33% 4-nitro-2-acetamidobenzoic acid, m. 225-6°. Nitration of 5-bromo-1-methylindoline with HNO₃-H₂SO₄ at below 0° in 1 hr. gave 100% red 6-nitro-5-bromo-1-methylindoline, m. 73-4°, which heated with chloranil as above gave 54% yellow 6-nitro-5-bromo-1-methylindole, m. 167-8°. Nitration of indoline in Ac₂O with fuming HNO₃ at 10-12° gave a solid acetyl derivative of 5-nitroindoline which refluxed 0.5 hr. with concentrated HCl gave yellow 5-nitroindoline (IV), 74%, m. 91-1.5°, and a little less soluble dinitroindoline, m. 243-4°. Similarly, 2-methylindoline gave 63% 5-nitro-2-methylindoline, m. 78-9°. IV with chloranil as above gave in 10 hrs. 68% 5-nitroindole, m. 135-7°. 5-Nitro-2-methylindoline similarly gave 65% 5-nitro-2-methylindole, m. 171.5-2.5°. Oxidation of 5-nitroindole in AcOH with CrO₃-H₂O 1 hr. gave 5-nitro-2-aminobenzoic acid, decomposing 275.2-6.0°, which refluxed 1 hr. with 50% H₂SO₄ gave p-nitroaniline. To 5.4 g. 5-nitroindole in 50 ml. EtOH was added a little Raney Ni followed by dropwise addition of 100 ml. N₂H₄.H₂O over several hrs. at reflux; the filtered solution gave 82% 5-aminoindole, b₆ 190°, decomposing 129-30°; Bz derivative m. 166-7°. Similar reduction of 5-nitro-2-methylindole gave 76% 5-amino-2-methylindole, m. 156-6.5°; Bz derivative m. 192-2.5°. Similarly, 6-nitro-2-methylindole gave 43% 6-amino-2-methylindole, b₄ 170-7°, m. 84-5°; Bz derivative m. 210°. 6-Nitroindole gave 77% 6-aminoindole, b₁ 138°, m. 67-8°; Ac derivative m. 269-71°. Heating 6-nitro-1-acetylindoline (3.8 g.) with 30 g. SnCl₂ in 20 ml. concentrated HCl 25 min. on a steam bath gave after addition of NaOH 89% 6-amino-1-acetylindoline, m. 179-9.5°. Reduction of 6-nitro-2-methylindoline with N₂H₄ as above gave 91% yellow 6-amino-2-methylindoline, b₁₇ 175-80°, m. 61-2°; HCl salt, decomposed 230-5°. Similarly, 5-nitroindoline gave 97% 5-aminoindoline, m. 678.5°, whose diacetyl derivative, m. 211-12.5°. Similarly was prepared 93% 5-amino-2-methylindoline, b₉ 155-8°, m. 92°. Bromination of 2-methylindoline with Br in AcOH in the presence of H₂SO₄ gave in 1 hr. 63.5% 5-bromo-2-methylindoline (V), b₃ 130-45° (some decomposition) crude, b₃ 132-3.5°, d₂₀ 1.4550, n_D²⁰ 1.6085; Bz derivative m. 157°. Similarly, indoline gave 72.7% 5-bromoindoline, b₂ 114-14.5°, 1.5240, 1.6311; Ac derivative m. 119-19.5°. V and chloranil, as above, gave 54% 5-bromo-2-methylindole, b₄ 155-62° (some decomposition), m. 97-8°; this with formalin and aqueous Me₂NH in AcOH gave 5-bromo-2-methylskatyldimethylamine, m. 145-7°. 5-Bromoindoline and chloranil gave 47% 5-bromoindole, m. 92-3°. Cf. Colo, et al., C.A. 49, 14733a. In the experiment, the researchers used many compounds, for example, 2-Methyl-6-nitro-1H-indole (cas: 3484-23-9SDS of cas: 3484-23-9).

Fujiwara, Kenshu et al. published their research in Tetrahedron Letters in 2007 | CAS: 14204-27-4

2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4) belongs to indole derivatives. Indole is an important structural motif of various drugs, therapeutic leads besides its prevalence in numerous natural products, agrochemicals, perfumery, and dyes.Indole was synthesized in moderate yield via an o-naphthoquinone catalyzed tandem cross-coupling of substituted aniline and benzylamine under aerobic oxidation conditions.Recommanded Product: 2-(Phenylthio)isoindoline-1,3-dione

Synthesis of the C8-C20 and C21-C30 segments of pectenotoxin 2 was written by Fujiwara, Kenshu;Aki, Yu-ichi;Yamamoto, Fuyuki;Kawamura, Mariko;Kobayashi, Masanori;Okano, Azusa;Awakura, Daisuke;Shiga, Shunsuke;Murai, Akio;Kawai, Hidetoshi;Suzuki, Takanori. And the article was included in Tetrahedron Letters in 2007.Recommanded Product: 2-(Phenylthio)isoindoline-1,3-dione This article mentions the following:

In this study, we synthesized the C8-C20 and C21-C30 segments, I and II, resp., of the diarrhetic shellfish toxin pectenotoxin 2. The C8-C20 segment I was assembled from a phosphonate, III, corresponding to the C8-C15 segment (prepared from L-malic acid in 19 steps) and an aldehyde, IV, corresponding to the C16-C20 segment (synthesized from 3-methyl-3-butenol in nine steps) by a twelve-step process including the Horner-Wadsworth-Emmons reaction, regio- and stereoselective reduction of the resulting enone, diastereoselective epoxidation, and 5-exo epoxide cleavage forming the C-ring. The C21-C30 segment II was constructed in 13 steps from (S)-glycidol via a route involving E-ring formation by 5-exo epoxide cleavage and stereoselective methylation at C27 by the Evans method. In the experiment, the researchers used many compounds, for example, 2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4Recommanded Product: 2-(Phenylthio)isoindoline-1,3-dione).

Nie, Guihua et al. published their research in Organic Chemistry Frontiers in 2021 | CAS: 774-47-0

5,6-Difluoroindoline-2,3-dione (cas: 774-47-0) belongs to indole derivatives. Indole, first isolated in 1866, and it is commonly synthesized from phenylhydrazine and pyruvic acid, although several other procedures have been discovered.Indole was synthesized in moderate yield via an o-naphthoquinone catalyzed tandem cross-coupling of substituted aniline and benzylamine under aerobic oxidation conditions.SDS of cas: 774-47-0

Umpolung of donor-acceptor cyclopropanes via N-heterocyclic carbene organic catalysis was written by Nie, Guihua;Huang, Xuan;Wang, Zhongyao;Pan, Dingwu;Zhang, Junmin;Chi, Yonggui Robin. And the article was included in Organic Chemistry Frontiers in 2021.SDS of cas: 774-47-0 This article mentions the following:

A N-heterocyclic carbene-catalyzed (NHC) formal umpolung of donor-acceptor (D-A) cyclopropanes was disclosed. The cyclopropane moiety was connected to an acetyl aldehyde that could be activated by a carbene catalyst. The initially electrophilic carbon attached to the donor group of the D-A cyclopropane aldehyde was inverted to form a nucleophilic reaction center. A subsequent reaction with isatins via a formal [3 + 2] process formed lactones I [R = H, 4-Br, 5-Me, etc.; R¹ = Bn, trityl; R² = OMe, OEt, O(i-Pr), OBn] bearing multiple functional groups with excellent enantio- and diastereoselectivities. In the experiment, the researchers used many compounds, for example, 5,6-Difluoroindoline-2,3-dione (cas: 774-47-0SDS of cas: 774-47-0).

Kovtunenko, V. A. et al. published their research in Khimiya Geterotsiklicheskikh Soedinenii in 1984 | CAS: 5388-42-1

2-Phenylisoindolin-1-one (cas: 5388-42-1) belongs to indole derivatives. The indole subunit is an almost ubiquitous component of biologically active natural products, and its study has been the focus of research for decades. More than 200 indole derivatives have already been marketed as drugs or are under advanced stages of clinical trials.Product Details of 5388-42-1

1-Ethylthio-2R-isoindoles. An example of nonsynchronous addition in the Diels-Alder reaction was written by Kovtunenko, V. A.;Dobrenko, T. T.;Voitenko, Z. V.;Tyltin, A. K.;Babichev, F. S.. And the article was included in Khimiya Geterotsiklicheskikh Soedinenii in 1984.Product Details of 5388-42-1 This article mentions the following:

Treating isoindolinones I (R = Me, Ph, p-MeC₆H₄, p-MeOC₆H₄, X = O) with P₂S₅ in refluxing pyridine gave 53-70% I (X = S) which were converted to 50-80% indolium salts II by treatment with Meerwein’s reagent. Treating II with dry base gave 45-50% III which underwent an non-synchronous Diels-Alder addition with N-phenyl- or N-(p-methoxyphenyl)maleimides to give 90% adducts IV (R¹ = p-MeOC₆H₄ or Ph) or V. In the experiment, the researchers used many compounds, for example, 2-Phenylisoindolin-1-one (cas: 5388-42-1Product Details of 5388-42-1).

Inoue, Kengo et al. published their research in Chemistry – A European Journal in 2021 | CAS: 14204-27-4

2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4) belongs to indole derivatives. Indole exists overwhelmingly in the 1H-indole form as do other simple indoles. Moreover, it is known that it controls biofilm formation. However, the role of indole in the cell has not been fully elucidated.Application In Synthesis of 2-(Phenylthio)isoindoline-1,3-dione

“Snapshot” Trapping of Multiple Transient Azolyllithiums in Batch was written by Inoue, Kengo;Feng, Yuxuan;Mori, Atsunori;Okano, Kentaro. And the article was included in Chemistry – A European Journal in 2021.Application In Synthesis of 2-(Phenylthio)isoindoline-1,3-dione This article mentions the following:

Recent developments in flow microreactor technol. have allowed the use of transient organolithium compounds that cannot be realized in a batch reactor. However, trapping the transient aryllithiums in a halogen dance is still challenging. Herein is reported the trapping of such short-lived azolyllithiums in a batch reactor by developing a finely tuned in situ zincation using Zn halide diamine complexes. The reaction rate is controlled by the appropriate choice of diamine ligand. The reaction is operationally simple and can be performed at 0° with high reproducibility on a multigram scale. This method was applicable to a wide range of brominated azoles allowing deprotonative functionalization, which was used for the concise divergent syntheses of both constitutional isomers of biol. active azoles. In the experiment, the researchers used many compounds, for example, 2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4Application In Synthesis of 2-(Phenylthio)isoindoline-1,3-dione).

Gao, Xing et al. published their research in Synthesis in 2016 | CAS: 14204-27-4

2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4) belongs to indole derivatives. Indole exists overwhelmingly in the 1H-indole form as do other simple indoles. Indole plays a fundamental role for QS in E. coli, being one of the signal molecules responsible for the transcription of a variety of genes (gabT, and tnaB ASTD). Application of 14204-27-4

Chiral Iminophosphorane Organocatalyzed Asymmetric Sulfenylation of 3-Substituted Oxindoles: Substrate-Interrelated Enantioselectivities was written by Gao, Xing;Han, Jianwei;Wang, Limin. And the article was included in Synthesis in 2016.Application of 14204-27-4 This article mentions the following:

Catalytic asym. sulfenylation of 3-substituted oxindoles has been developed through efficient catalysis by tartaric acid derived chiral iminophosphoranes. With N-(phenylthio)phthalimide as the sulfur source, a wide range of optically active 3-phenylthiooxindoles were obtained in excellent yields (90-99%) and good enantiomeric excess (up to 90% ee). Interestingly, 3-aryl and 3-Me substituted oxindoles afforded sulfenylated products I (R¹ = Ph, Me, 2-naphthyl, 4-MeC₆H₄, 4-MeOC₆H₄, 4-FC₆H₄; R² = H, 5-Me, 5-MeO, 5-F, etc.) in S-configuration, whereas substituted oxindoles with 3-arylidene or 3-iso-Bu substituents gave the corresponding R-configured sulfenylated products II (R¹ = Bn, i-Bu, 4-MeC₆H₄CH₂, 4-MeOC₆H₄CH₂, 4-FC₆H₄CH₂; R² = H, 5-Me, 5-MeO, 5-F, etc). In the experiment, the researchers used many compounds, for example, 2-(Phenylthio)isoindoline-1,3-dione (cas: 14204-27-4Application of 14204-27-4).