Detail of "787-84-8"

Reference

Cyclodehydrations using chlorosulfonic acid-dimethylformamide

Cyclodehydrations using chlorosulfonic acid-dimethylformamide. Convenient method for the synthesis of 1,3,4-oxadiazoles from diaroylhydrazines. Chiriac, Constantin I. (Inst. Chim. Macromol. "Petru Poni", Iasi, Rom.). Rev. Chim. (Bucharest), 34(12), 1131-2 (Romanian) 1983. CODEN: RCBUAU. DOCUMENT TYPE: Journal CA Section: 28 (Heterocyclic Compounds (More Than One Hetero Atom)) Hydrazides RCONHNHCOR1 (R = Ph, p-tolyl, p-anisyl, 3-BrC6H4; R1 = Ph, p-anisyl, 4-ClC6H4, p-tolyl, 3- and 4-BrC6H4) underwent cyclocondensation to oxadiazoles (I). A mixt. 6781-59-5 and 787-84-8 are just another two chemicals used in this study. of PhCONHNHCOPh, ClSO3H, and DMF was heated 3 h at 100-10° to give I (R = R1 = Ph). .

Device and methods for producing N,N'-diaroylhydrazines

Device and methods for producing N,N'-diaroylhydrazines. Von Gentzkow, Wolfgang; Schmiedel, Manfred; Tussing, Reinhold (Siemens A.-G. , Fed.Several substances are used for example 787-84-8 and 9003-27-4 which are their cas registry numbers. Rep. Ger.). Ger. Offen. DE 3210859 A1 29 Sep 1983, 14 pp. (German). (Germany). CODEN: GWXXBX. CLASS: IC: C07C109-10. APPLICATION: DE 82-3210859 24 Mar 1982. DOCUMENT TYPE: Patent CA Section: 37 (Plastics Manufacture and Processing) Section cross-reference(s): 25 N,N'-Diaroylhydrazines such as N,N'-disalicyloylhydrazine (I) [23647-78-1] are prepd. by the reaction of carboxylic acid alkyl esters with hydrazine or monoaroylhydrazines in a reaction medium which has low volatility and is a liq. or gas at the reaction temp. The volatiles (alc.-water) are distd. off during the reaction. After the reaction is complete, the contents of the reactor are pumped through a dispersing app. to pulverize the crystals and then returned to the top of the reactors which contains a rotating disk functioning as a centrifugal thin-film evaporator for removal of the remaining volatiles. The pasty products contg. salicyloyl groups are specially suitable as stabilizers for protecting polyolefins against Cu-catalyzed oxidative degrdn. during contact with elec. conductors. The use of pastes avoids the eye irritation encountered with powders. Thus, 2.714 kg Vaseline contg. 0.5 kg H2NNH2.H2O and 3.040 kg Me salicylate [119-36-8] was heated to 120° during 3 h with distn. of MeOH and water, mixed with 30 g B trioxide, and heated 150° for 3 h with removal of volatiles. The pasty product was pumped through the dispersing app. to pulverize the crystals and then returned to a rotating disk in the top of the reactor to remove volatiles and cool the paste to 80°. The yield of I was 80%. .