Guanidine carbonate, preparation

Cycloalkane ring-fused 2,4-diaminopyrido[2,3-, pyrimidine 580 was obtained by direct treatment of sulfone 579 with guanidine carbonate in boiling diphenyl ether. Sulfoxide 579 was prepared by perbenzoic acid oxidation of the methylthio derivative <1994T199>. 

Preparation of Guanidine Carbonate from Nitrogvanidine. Two hundred and eight grams of nitroguanidine, 300 grams of ammonium carbonate, and 1 liter of water are heated together in a 2-liter flask in the... 

Normal nucleophilic substitution occurred on treatment of 2-carbamoyl-3-chloropyrazine with alcoholic methylamine at 130° (423, 836) 2-chloro-3-(4 -morpholinocarbonyOpyrazine with morpholine at reflux in benzene (867) 2dimethyl sulfoxide at 65° (857) and cyclohexylamine in benzene at reflux (946) 3-chloro-2-methoxycarbonyl-5-phenylpyrazine with alcoholic methylamine at 140° (375) 2-carboxy-3-chloropyrazine with anhydrous ammonia at 100° for 5 hours (947) 2-carbamoyl-6-chloropyrazine with aqueous methylamine at reflux (940) 2-chloro-6-(4 -morpholinocarbonyl)pyrazine (and other amides) and 2-chloro-6-methoxycarbonylpyrazine with morpholine (and other amines) (870, 948, 949) and 2-chloro-6-methoxycarbonylpyrazine with liquid ammonia at 80° (870). 2-Chloro-3-methoxycarbonylpyrazine fused with guanidine carbonate gave 2-amino4-hydroxypteridine and its 7-methyl-, 7-phenyl, and 6,7-diphenyl analogues were prepared similarly (371,375). 

A synthesis of the 8,13-diaza-oestrone (477) via cyclisation of (476) has been described.Condensation of the -diketone (479), obtained by alkylation of the morpholine enamine of 6-methoxytetralone, with guanidine carbonate or hydrazine has been used to prepare the 11,13-diaza-steroids (480) and (478) respectively (see Scheme 8). 

A common method for the preparation of 2,4(1//,3//)-quinazolinediones (627) consists of fusion of anthranilic acid derivatives with urea (Scheme 100). The benzene ring is frequently substituted . The most satisfactory synthesis of 2-aminoquinazoline (628) is by the reaction of guanidine carbonate with o-aminobenzaldehyde in boiling decalin. Cyanamide or dicyanamide can be used instead of guanidine carbonate . 

A -formyl group. Subsequently, dl-(VIII.64) was prepared by a modified Taylor synthesis by Rosowsky et al. [265], 4-(7V-Methyl-A -tosylamino)benzoyl chloride was condensed with diethyl DL-3-aminoglutarate, the tosyl group was removed with HBr, the resultant amine was coupled to 2-amino-5-chlorome-thyl-3-cyanopyrazine A -oxide [24], and the 7V-oxide was directly reduced to amino nitrile dl-(VIII.66) with triethyl phosphite and condensed with guanidine carbonate to form diester dl-(VIII.64) in low yield. 

The heterocycle (XVI), for sulfometuron methyl can be prepared by the reaction of acetyl acetone and guanidine carbonate as shown (H) (Equation 13). 

This Fmoc analog is prepared from the chloroformate, O-succinimide, or p-nitrophenyl carbonate and is cleaved with 10% piperidine in 1 1 6M guanidine/IPA. It was designed to interact strongly on a column of porous graphitized carbon so as to aid in the purification of peptides after cleavage from the resin. 

One such compound, bropirimine (112), is described as an agent which has both antineo-plastic and antiviral activity. The first step in the preparation involves formation of the dianion 108 from the half ester of malonic acid by treatment with butyllithium. Acylation of the anion with benzoyl chloride proceeds at the more nucleophilic carbon anion to give 109. This tricarbonyl compound decarboxylates on acidification to give the beta ketoester 110. Condensation with guanidine leads to the pyrimidone 111. Bromination with N-bromosuccinimide gives bropirimine (112) [24]. 

Borane, 1-methylbenzylaminocyanohydropyrrolyl-, 3, 84 Borane, thiocyanato-halogenohydro-, 3,88 Borane, trialkoxy-amine complexes, 3, 88 Borane, triaryl-guanidine complexes, 2,283 Borane, trifluoro-complexes Lewis acids, 3,87 van der Waals complexes, 3, 84 Borane complexes aminecarboxy-, 3,84 aminehalogeno-, 3, 84 amines, 3, 82, 101 B-N bond polarity, 3, 82 preparation, 3, 83 reactions, 3, 83 bonds B-N, 3, 88 B-O, 3, 88 B-S, 3, 88 Jt bonds, 3, 82 carbon monoxide, 3, 84 chiral boron, 3, 84 dimethyl sulfide, 3, 84 enthalpy of dissociation, 3, 82... 

Benzoguanamine has been prepared by the reaction of dicyandiamide with benzonitrile in a sealed tube at 220-230°,2 with an excess of benzonitrile in the presence of piperidine and potassium carbonate,3 with benzonitrile in a solvent in the presence of a basic catalyst,4 and with benzamidine hydrochloride at elevated temperatures.5 It has also been prepared from the reaction of biguanide acetate with benzamidine hydrochloride,5 or of bigua-nide sulfate with benzoyl chloride in an alkaline medium,7 and by the distillation of guanidine benzoate.5... 

Examples of syntheses in which the heterocyclic ring is generated by cyclization of an exocyclic amine to an electrophilic carbon atom include the preparation of triazolo[4,3-6]triazoles (137) by elimination of alkanethiol from guanidine derivatives 136137 (cf. 132 - 133), and many examples (mostly in patents) of pyrazolo[l,5-a]benzimidazoles prepared according to Eq. (18).138-142... 

Carbamate-bound guanidines have been prepared by the condensation of amines with thioureas linked to insoluble supports as carbamates [519]. The direct reaction of guanidines with resin-bound carbonates or other alkoxycarbonylating agents requires the use of chloroformates or other reactive carbonic acid derivatives [520,521], Carbamate-bound amidines (Entries 7 and 8, Table 3.28) have been prepared by the reaction of amidines with resin-bound 4-nitrophenyl carbonates (0.9 mol/L amidine in DMF/DIPEA, > 4 h [522-524]). 

Practically all methods which have been proposed for the preparation of guanidine salts involve either ammonation or ammonolysis of some derivative of carbonic acid. Phosgene,1 chloropicrin,2 and esters of orthocarbonic acid2 react with aqueous ammonia to give small yields of guanidine. The hydrochloride is obtained when carbon tetrachloride3 is acted upon by liquid ammonia under pressure. Urea4 is partially ammonolyzed in the presence of ammonium chloride. 

J.P.Picard M.Blais A New Approach to the Synthesis of Calcium Cyanamide without Using Electrical PowerM> PATR 2261 (1955) (Conf) 14)Sax (1957), 426 WJ.P. Picard V.LSiele, "Mechanism of Formation of White Calcium Cyanamide by the Picatinny Process . PATR 2405 (1957) (Conf) l6)J.P. Picard et al, "Laboratory Pilot Plant Investigation of Picatinny Process for Producing White Calcium Cyanamide , PATR 2452 (1957) (Conf) 17)V.I.Siele et al, "Suitability of White Calcium Cyanamide for the Preparation of Guanidine Nitrate , PATR 2455 (1957) (Conf) 18)M.Blais J.P.Picard, "Effect of Various Physical Properties of Lime on the Purity of White Calcium Cyanmide Made by the Picatinny Process , PATR 2457 (1857) (Conf) 19)S. Chard et al, "The Manufacture of Calcium Cyanamide Via Carbon Monoxide, Ammonia and Reactive Lime Parti. Laboratory Work ERDE Rept 2/R/57 (1957) (Conf), and "Part II. An Assessment of the Possible Procedure... 

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