Day: January 5, 2023

2-Amino-4(or 5)-arylthiazoles. I. Ultraviolet absorption spectra of alkyl- or phenyl-substituted compounds was written by Okamiya, Jiro. And the article was included in Nippon Kagaku Zasshi in 1959.SDS of cas: 6318-74-7 This article mentions the following:

Ultraviolet absorption spectra were reported for 2-aminothiazole, 2-amino-4-methylthiazole, 2-amino-5-methylthiazole, 2-amino-4-ethyl-5-methylthiazole, 2-amino-4,5-tetramethylenethiazole, 2-amino-4,5-benzothiazole, 2-amino-4-phenylthiazole, 2-amino-5-phenyl-5-methylthiazole, 2-amino-4-(p-tolyl)thiazole, 2-amino-4-(o-tolyl)thiazole, 2-amino-4-(o-tolyl)-5-methylthiazole, m. 124°, 2-amino-4-mesitylthiazole, m. 169°, 2-amino-4-mesityl-5-methylthiazole, m. 123-4°, 2-amino-5-phenylthiazole, 2-amino-4-methyl-5-phenylthiazole, m. 171°, 2-amino-4,5-diphenylthiazole, 2-amino-4-(p-tolyl)-5-phenylthiazole, m. 179°, 2-amino-4-phenyl-5-(p-tolyl)thiazole, m. 176°, 2-amino-4,5-bis(p-tolyl)thiazole, m. 167°, 2-amino-4,5-dihydronaphtho[1,2]thiazole, 4,4′-bis(2-amino-4-thiazolyl)bibenzyl, m. 230-45° (decomposition), 2,2′-diamino-4,4′-diphenyl-5,5′-bithiazolyl (I), 1,2-bis(2-amino-4-phenyl-5-thiazolyl)ethane, m. 238°, 1,5-bis(2-amino-4-phenyl-5-thiazolyl)pentane (II), m. 165°, and 1,6-bis(2-amino-4-phenyl-5-thiazolyl)hexane. Spectra of alkyl derivative were almost the same. Spectra of 4-phenyl compounds had maximum at longer wave lengths than those of 4-phenyl-5-alkyl compounds, indicating the presence of steric hindrance. II had twice the intensity of other thiazoles, while I was weaker because of steric effects. The 5-phenyl compounds had maximum at longer wave lengths than the 4-phenyl compounds 4,5-Diaryl compounds seemed to have a fair amount of resonance (from the spectra), in spite of the expected steric hindrance. In the experiment, the researchers used many compounds, for example, 4,5-Diphenylthiazol-2-amine (cas: 6318-74-7SDS of cas: 6318-74-7).

4,5-Diphenylthiazol-2-amine (cas: 6318-74-7) belongs to thiazole derivatives. Thiazole is a five-membered, unsaturated, planar, π-excessive heteroaromatic containing one sulfur atom and one pyridine-type nitrogen atom at position 3 of the cyclic ring system. Electrophilic attack at nitrogen depends on the presence of electron density at nitrogen as well as the position and nature of substituent linked to the thiazole ring.SDS of cas: 6318-74-7

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Sequencing Groebke-Blackburn-Bienayme and Aza-Michael Addition Reactions: A Modular Strategy for Accessing a Diverse Collection of Constrained Benzoxazepine and Imidazopyrazine Systems was written by Srinivasulu, Vunnam;Al-Marzooq, Farah;Hamad, Mohamad;Khanfar, Monther A.;Ramanathan, Mani;Soares, Nelson C.;Al-Tel, Taleb H.. And the article was included in Synthesis in 2021.Application In Synthesis of 4,5-Diphenylthiazol-2-amine This article mentions the following:

A divergent strategy that permitted the access to diversely functionalized benzoxazepinium scaffolds fused to various heterocycles was reported. The described strategy featured a one-pot combination of the Groebke-Blackburn-Bienaym reaction and an aza-Michael addition Me (E)-4-(2-formylphenoxy)but-2-enoates were utilized as central elements in this cascade. These building blocks were reacted with a variety of functionalized amino-azines and tert-Bu isocyanide under ytterbium triflate [Yb(OTf)₃] catalysis. The cascade represented a rapid, modular and atom-economic process that leaded to the construction of a diverse collection of constrained benzoxazepinium systems from a wide substrate scope. In the experiment, the researchers used many compounds, for example, 4,5-Diphenylthiazol-2-amine (cas: 6318-74-7Application In Synthesis of 4,5-Diphenylthiazol-2-amine).

4,5-Diphenylthiazol-2-amine (cas: 6318-74-7) belongs to thiazole derivatives. Thiazole rings are planar and aromatic. Thiazoles are characterized by larger pi-electron delocalization than the corresponding oxazoles and have therefore greater aromaticity. Electrophilic attack at nitrogen depends on the presence of electron density at nitrogen as well as the position and nature of substituent linked to the thiazole ring.Application In Synthesis of 4,5-Diphenylthiazol-2-amine

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

An approach to the synthesis of 4-phenyl-5-(arylimino)-Δ²-1,2,3,4-thiatriazolines was written by L’Abbe, Gerrit;Franek, Walter;Toppet, Suzanne;Delbeke, Pieter. And the article was included in Journal of Heterocyclic Chemistry in 1990.Reference of 1843-21-6 This article mentions the following:

4-Phenyl-5-arylimino-Δ²-1,2,3,4-thiatriazolines I (R = Ph, 4-MeC₆H₅) are presumably formed by reacting 5-arylaminothiatriazoles II with benzene at 50°, but decompose in situ to benzothiazole derivatives III. The reaction mechanism is discussed. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6Reference of 1843-21-6).

N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. The higher aromaticity of thiazole is due to delocalization of a lone pair of sulfur electrons across the ring, which is evidenced by chemical shifts of ring hydrogen at δ 7.27 and 8.77 ppm (C2 and C4), indicating diamagnetic ring current. The pyridine-type nitrogen in the thiazole ring deactivates the ring for electrophilic substitution reactions, which is further reduced in acid due to protonation of the thiazole ring.Reference of 1843-21-6

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

Structure of phenyl isothiocyanate and methyl isothiocyanate sulfides was written by Paranjpe, M. G.. And the article was included in Indian Journal of Chemistry in 1968.Computed Properties of C13H10N2S This article mentions the following:

“Phenyl isothiocyanate sulfides” (I) or “methyl isothiocyanate sulfide” (II) gave the tabulated RNHCSNHR1 (III) when treated with R1NH2 in “sulfide”-amine ratios 1:>2. Reaction of I or II with R1NH2 in ratios 1:<1 90-120 min. gave, resp., R1NHCSNPhCSNHPh (IV) or R1NHCSNMeCSNHMe (V) as well as III. Refluxing CHCl3 was used with I; with II the reaction temperature was 100°, but no solvent was used (reactant “sulfide”, R1, R, m.p. of IV or V, and m.p. of III given): I, PhCH2, Ph, 129°, 148; I, cyclohexyl, Ph, 135°, 149°; I, Bu, Ph, 145°, 68°; I, sec-Bu, -, 140°, -; II, PhCH2, PhCH2, 109°, 149° [also obtained was III (R = Me), m. 78°]; II, cyclohexyl, cyclohexyl, 138°, 179°. [TABLE OMITTED] On warming IV (R1 = PhCH2) (VI) with Na plumbite solution desulfurization was observed. Boiling VI with aqueous MeNH2 afforded III (R = Ph, R1 = Me) and III (R = Ph, R1 = PhCH2). VI (1 g.), 0.8 ml. PhCH2Cl, and 20 ml. EtOH, refluxed 5 hrs. gave the 3-benzyl analog, m. 154° (EtOH), which with alc. NH4OH decomposed into III (R = Ph, R1 = PhCH2). VI (2 g.) in 40 ml. dry CHCl3, treated with Br in CHCl3 until color persisted, yielded a hydrobromide, m. 228°, which on basification yielded the free base, 2-phenylaminobenzothiazole, m.p. and mixed m.p. 158°. Thus the identity of VI was determined A mixture of 8 g. 1,3-dimethylthiourea, 8 ml. PhCH2Cl, and 50 ml. EtOH was refluxed 90 min., cooled, basified (NH4OH), and extracted with C6H6. The dried extract was kept overnight with 8 ml. CS2 and treated with 12 g. Br in 40 ml. C6H6 to give a hydrobromide, m. 236°, which on NH4OH basification gave 3.8 g. 4-methyl-5-methylimino-1,2,4-dithiazolidine-3-thione (II), m. 86° (identical with an authentic sample), which on warming with EtOH yielded the isomer (VII), m.p. and mixed m.p. 120° (Freund, 1904, 1895). Ir spectra of I and II are reported. In the experiment, the researchers used many compounds, for example, N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6Computed Properties of C13H10N2S).

N-Phenylbenzo[d]thiazol-2-amine (cas: 1843-21-6) belongs to thiazole derivatives. Thiazole is a five-membered, unsaturated, planar, π-excessive heteroaromatic containing one sulfur atom and one pyridine-type nitrogen atom at position 3 of the cyclic ring system. The nitrogen in thiazole is sp2 hybridized and the lone pair of electrons localized on the nitrogen is less reactive due to increased aromatic character and decreased basicity. It is protonated and alkylated/acylated at nitrogen forming hydrochloride and quaternary thiazolium salt.Computed Properties of C13H10N2S

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica

One pot synthesis using supported reagents system KSCN/SiO₂-RNH₃OAc/Al₂O₃: synthesis of 2-aminothiazoles and N-allylthioureas was written by Aoyama, Tadashi;Murata, Sumiko;Arai, Izumi;Araki, Natsumi;Takido, Toshio;Suzuki, Yoshitada;Kodomari, Mitsuo. And the article was included in Tetrahedron in 2006.Quality Control of 4,5-Diphenylthiazol-2-amine This article mentions the following:

A simple and efficient method has been developed for the synthesis of 2-aminothiazoles and N-allylthioureas from com. available materials in one pot by using a supported reagents system, KSCN/SiO₂-RNH₃OAc/Al₂O₃, in which α-halo ketones react first with KSCN/SiO₂ and the product, α-thiocyanatoketone, reacts with RNH₃OAc/Al₂O₃ to give the final products, 2-aminothiazoles, in good yield. Allyl bromides react with KSCN/SiO₂ and the products, allyl isothiocyanates, react with RNH₃OAc/Al₂O₃ to give N-allylthioureas. In the experiment, the researchers used many compounds, for example, 4,5-Diphenylthiazol-2-amine (cas: 6318-74-7Quality Control of 4,5-Diphenylthiazol-2-amine).

4,5-Diphenylthiazol-2-amine (cas: 6318-74-7) belongs to thiazole derivatives. Thiazole is a five-membered, unsaturated, planar, π-excessive heteroaromatic containing one sulfur atom and one pyridine-type nitrogen atom at position 3 of the cyclic ring system. The pyridine-type nitrogen in the thiazole ring deactivates the ring for electrophilic substitution reactions, which is further reduced in acid due to protonation of the thiazole ring.Quality Control of 4,5-Diphenylthiazol-2-amine

Referemce:
Thiazole | C3H3NS – PubChem,
Thiazole | chemical compound | Britannica