Tosyl hydrazide

A useful reaction in early preparations of parent pyridopyrimidines was the McFadyen-Stevens decomposition of tosyl hydrazides, e.g. (93) -> (3) (62JCS4094). 

Tile easy availability of (di)nitronaphthyridones, in which the lactam part can easily be converted into an iminochloride, has successfully led to preparation of the parent (di)nitronaphthyridines by removal of the chloro atom. For that purpose the chloro atom in the 2- and 4-chloro derivative of the 3-nitro-l,5-, -1,6-, and -1,8-naphthyridines (78a-78e) was first substituted with tosylhydrazine to give the corresponding tosyl-hydrazide, which then was hydrolyzed in alkaline solution into the corresponding 3-nitro-l,5-, -1,6-, and -1,8-naphthyridines (79a, 79b, and 79c). 

Deuterio-3-iiitro-l,6-iiaphthyridiiie (168) was prepared from 4-chloro-3-iiitro-l,6-iiaphthyridiiie (166) by a reaction with tosyl hydrazide and subsequent hydrolysis of the 4-tosylhydrazino derivative (167) with Na2C03/ D2O solution (83RTC359). 7-Deuterio-l,8-naphthyridin-2(lH)-one was prepared by heating l,8-naphthyridin-2(lH)-one with deuterium oxide at 230°C for 35 h (85JHC761). Tliis deuterio compound could be converted into 2-chloro-(or 2-ethoxy-) 7-deuterio-3,6-dinitro-l,8-naphthyridine. 

When a solution of phenacyl halide 258 and excess tosyl hydrazide in methanol is heated to reflux, l-(tosylamido)-4-aryltriazole 261 is formed. The reaction proceeds presumably via dihydrazide derivative 259 that subsequently undergoes intramolecular cyclocondensation to triazoline 260. In the following step, the triazoline must be oxidized to the final triazole product 261. Mechanism of the oxidation is not quite clear, but the probable oxidant is the starting phenacyl halide, as a half of it is converted to the corresponding acetophenone tosylhydrazone that is isolated as the main side product of the reaction (Scheme 37) <2004H(63)1175>. 

A parallel synthesis of 1,2,3-thiadiazoles employing a catch-and-release strategy has been reported using the Hurd-Mori reaction. A polymer-bound tosyl hydrazide resin reacted with a-methylene ketones to afford a range of sulfonyl hydrazones. Treatment of these sulfonyl hydrazones with thionyl chloride causes 1,2,3-thiadiazole formation and cleavage of the resin in one step <1999JOC1049>. 

Precursors for this task were obtained by addition of /-butylmagnesium bromide to the central bond of [1.1.1 ]propellane 40a followed by conversion of the 3-f-butylbicyclo[ 1.1.1 Jpentyl-1 -y 1-magnesium bromide (88) into the ketones 89 by standard methods.27 Reaction of ketones 89 with tosyl hydrazide afforded the hydrazones 90, which gave the corresponding lithium salts 91 by reaction with MeLi in ether. These salts were dried under high vacuum and then pyrolized at 4 x 10 5 torr in the temperature range of 100-130°C and the volatile products condensed in a liquid nitrogen-cooled trap. 

Redaction of / -toluenesulfonyIhydrazides by complex hydrides yidds hydrocarbons. The TV -tosyl hydrazide of stearic acid gave a 50-60% yield of octa-decane on reduction with lithium aluminum hydride [577]. 

The keto group in condensed 4//-pyran derivative 264 was successfully reduced by reduction of the tosyl hydrazide with sodium borohydride.290... 

N-Tosylglycine ethyl ester, 703 Tosyl hydrazide, see p-Toluenesulfonyl-hydrazide... 

In a similar manner to that for pyridines, pyridazines 68 were synthesized from functionalized hydrazines 66 via pyridazones 67 using an RCM/elimination/ triflation approach (09CC3008). The metathesis precursors 66 were synthesized in two steps from commercially available tosyl hydrazide (not shown). Substituents can be incorporated at aU ring positions, which was clearly exemplified by the introduction of a methyl group in different positions of the pyridazine (Scheme 19). 

A computational study has been undertaken of the reaction between dimethyl perflu-orododecanedicarboxylate and alkyl ketones, to give polyfluorinated tetraketones. 2 -Benzoyl-biphenyl-2-carbaldehyde (161) can be converted into a phenanthrol derivative (162), using tosyl hydrazide (TSNHNH2) in toluene at 70 The reaction proceeds via selective formation of the A-tosylhydrazone at the aldehyde, followed by cyclization (using a strong base). The reaction is formally similar to a diazo-carbon... 

Synonyms Benzenesulfonic acid, 4-methyl-, hydrazide Hydrazine, p-tolylsulfonyl- p-Toluenesulfonhydrazide p-Toluenesulfonic acid, hydrazide p-Toluenesulfono-hydrazide p-Toluenesulfonyl hydrazide N-Toluolsulfonyl hydrazine Tolylsulfonyl hydrazine Tosyl hydrazide... 

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