Diethylamino 4-methoxyphenyl

Synonym A/-[2-[(2-Bromo-4,6-dinitrophenyl)azo]-5-(diethylamino)-4-methoxyphenyl]acetamide Source Shim, J.-J. Baek, J.-K. Sung, H.-D. Lee,... 

Diethylamino-4-(4-methoxyphenyl)-isothiazole 5,5-dioxide 6 is (95T(51)2455) a highly reactive partner in 1,3-dipolar cycloadditions with several dipoles. Azomethine yhdes, such as oxazolones 7 and miinchnones 8, afforded with 6 bicychc pyrrolo[3,4-d]isothiazole 5,5-dioxides 9, 10, 11 in satisfactory yield. The regioselectivity of the reaction was excellent. The thermal behavior of these new bicychc systems was investigated. When heated at their melting point or shghtly above, triarylpyrroles 12, 13 were obtained through SOj and AtiV-diethylcyanamide ehmination. 

In the presence of various metal ions, 2-(fluoroenone)benzothiazoline has been found to rearrange to A-2-mercaptophenylenimine, while a free radical mechanism involving the homolysis of C-S and C-N bonds has been invoked to explain the formation of 3-phenyl-1,2,4-triazole derivatives from the thermal fragmentation and rearrangement of 2-(arylidenehydrazino)-4-(5//)-thiazolone derivatives. The cycloadducts (36) formed from the reaction of 3-diethylamino-4-(4-methoxyphenyl)-5-vinyl-isothiazole 1,1-dioxide (34) with nitric oxides or miinchnones (35) have been found to undergo pyrolytic transformation into a, jS-unsaturated nitriles (38) by way of pyrrole-isothiazoline 1,1-dioxide intermediates (37). 

Clerici et al. studied the reaction of 3-diethylamino-4-(4-methoxyphenyl)-5-vinyl-isothiazole 1,1-dioxides 15 with nitrile oxides and with munchnones. These reactions produced cycloadducts such as 16 and 17 which underwent thermal rearrangement to a, P-unsaturated nitriles <98T11285>. 

The reaction of sodium azide with 5-substituted 3-diethylamino-4-(4-methoxyphenyl)-isothiazole 1,1-dioxides afforded [l,2]thiazete 5,5-dioxides 56. It has been proposed that a nucleophilic addition of the azide ion to C-5 followed by ring closure gave a triazoline intermediate, which cyclized intramolecularly with concomitant nitrogen extrusion <02T5173>. 

Abbreviations Ac acetyl Bn benzyl BSP 1-benzenesulfinyl piperidine BTIB bis(trifluoroacetoxy)iodobenzene DAST (diethylamino)sulfur trifluoride DDQ 2,3-dichloro-5,6-dicyano-/)-benzoquinone DMDO dimethyldioxirane DMTSF dimethyl(methylthio)sulfonium tetrafluoroborate DMTST dimethyl(methylthio)sulfonium triflate DTBMP 2,6-Ai-tert-butyl-4-methylpyridine DTBP 2,6-di-tert-butylpyridine DTBPl 2,6-di-tert-butylpyridinium iodide FDCPT l-fluoro-2,6-dichloropyridinium triflate FTMPT l-fluoro-2,4,6-trimethylpyridinium triflate IDCP iodonium dicollidine perchlorate IDCT idonium dicollidine triflate LPTS 2,6-lutidinium p-toluenesulfonate LTMP lithium tetramethylpiperidide Me methyl MPBT S-(4-methoxyphenyl) benzenethiosulflnate NBS A-bromosuccinimide NIS A-iodosuccinimide NlSac A-iodosaccharin PPTS pyridinium p-toluenesulfonate TBPA tris(4-bromophenyl)ammoniumyl hexachloroantimonate Tf trifluoromethanesulfonyl TMTSB methyl-bis(methylthio)sulfonium hexachloroantimonate TMU tetramethylurea Tr trityl TTBP 2,4,6-tri-tert-butylpyrimidine. 

Acetylamino-4-diethylamino-5-methoxyphenyl)-5-ammo-7-bromo-4-chloro-2//-... 

Sodium azide, ethanol, and acetone react with 3-diethylamino-4-(4-methoxyphenyl)isothiazole... 

The average AV of -16 + 1 cm mol and the solvent independence of the process suggested that the reaction follows a nonpolar concerted, synchronous one-step mechanism. The observed pressure acceleration is very similar to that found for the insertion of dipropylcyanamide and l-(diethylamino)propene into the metal-carbene bond of pentacarbonyl(methoxyphenyl-carbene)chromium and -tungsten (shown in Scheme 1.2) for which varies between —17 and —25 cm mol ... 

Propanidid. 4-[2.(Diethylamino)-2-axoethoxy]-3 methoxybenzeneacetic acid propyl ester [4-[(diethylca rbamo-yl)methoxy]-3-methoxyphenyl]acrtic acid propyl ester [3-met hoxy -4 [(W, N-die thy Icarba mi do)met h oxyjphen yljacet ic... 

Propyl 4-[(diethylcarbamoyl)-methoxy]-3 methoxyphenyl acetate Benzene-acetic acid, 4-[2-(diethylamino)-2-oxoethyl]-3-methoxy-, propyl ester B.P.,... 

Diethylamino-4-(4-methoxyphenyl)isothiazole-1,1-dioxide (17 Ar = 4-MeOPh) on treatment with one equivalent of bromine gave the dibromo derivative (18) which upon heating or by reaction with triethylamine furnished the mono bromo compound (19) on elimination of HBr. Palladium catalysed coupling of (19) with a variety of organostannanes provided good yields of 5-substituted isothiazoles (20) <97T15859>. 

Tin Reagents. Vinyltrialkyltin reagents can be used for introduction of alkenyl substituents into the 4-position in N-protected imidazoles 130 (Scheme 55). In this particular case alkenylation reaction under Heck conditions was unsatisfactory due to facile homocoupling of the heterocycle. A related series of reactions has been used for introduction of an allylic alcohol substituent into the imidazole 4-position in a ribosylimidazole nucleoside 131.Vinylation of 5-bromo-3-diethylamino-4-(4-methoxyphenyl)isothiazole 1,1-dioxide 132 with vinylstannane reagents can be used for the preparation of 5-alkenylated isothiazole 1,1-dioxides. "... 

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