Cyclopropane carboxylic acid chloride

Amino-5-chlorobenzophenone Cyclopropane carboxylic acid chloride Phthalimidoacetyl chloride... 

Preparation of 2-Cyclopropylcarbony/amido-5-Chlorobenzophenone To 400.5 g (1.73 mols) of 2-amino-5-chlorobenzophenone dissolved in 220 g (2.18 mols) of triethylamine and 3.5 liters of tetrahydrofuran is added cautiously 181 g (1.73 mols) of cyclopropane-carboxylic acid chloride. The reaction is refluxed 2 /2 hours and allowed to cool to room temperature. The solvent is then removed under vacuum to obtain 2-cyclopropylcarbonyl-amido-5-chlorobenzophenone as a residue which is dissolved in 1 liter of methylene chloride, washed twice with 5% hydrochloric acid, and then twice with 10% potassium hydroxide. The methylene chloride solution is then dried over anhydrous magnesium sulfate, filtered and the solvent removed under vacuum. The residue is recrystallized from 1,500 ml of methanol, charcoal-treating the hot solution to give 356 g of 2-cyclopropylcarbonylamido-5-chlorobenzophenone, MP 105° to 105.5°C (69% yield). 

Cyclopropane carboxylic acid chloride cyprofuram, profluralin, trinexapac Cyclopropylamine cyprazine, cyromazine, procyazine Cyclopropyl p.chloro phenyl ketone flucycloxuron... 

Weinstock reaction of NaNs with the mixture of the acid (14) and ethyl chloroformate instead of the acid chloride prevented isomerization of the cyclopropane-carboxylic acid chloride (16, R = H) which occasionally occurred with the former procedures. No isomerizations were reported when the azide (15) was prepared via the hydrazide from the ester. 

Ethyl cycfopropane-carboxylate. Use 22 g. of cyclopropane-carboxylic acid (Section V,33) and 40 g. (24-6 ml.) of redistilled thionyl chloride to prepare the acid chloride, b.p. 118-119 (22 g.). Treatthe latter with 10 g. of absolute ethyl alcohol. The yield of ethyl cyclo-propane-carboxylate, b.p. 132-133 , is 13 g. 

Carboxylic acid fluorides from carboxylic acid chlorides with formation of cyclopropanes from halides... 

The Faworski-rearrangement of a-halocyclobutanones provides a very attractive and in practice, often particularly useful method [488-491], since it usually utilizes readily available acid chlorides and olefins as precursors. Not only the commercially important (fenpropathrin) tetramethyl cyclopropane carboxylic acid 247 as in Reaction scheme 169, but many others, particularly higher alkyl-substituted cyclopropane carboxylic acids are preferentially prepared in this way (Reaction scheme 170). 

In browsing through my notes I discovered that I had made another N-substitution product of DOM. Efforts to fuse free-base DOM with the ethyl cyclopropane carboxylate failed, but the reaction between it and the acid chloride in pyridine gave the corresponding amide, with a mp of 156-157 deg C from MeOH. Anal. (C16H23N03) C,H,N. This reduced smoothly to the corresponding amine,... 

Interestingly, some nucleophiles attack the central carbon of the r-allyl system 198 to form the palladacyclobutane 199 and reductive elimination produces the cyclopropanes 200. Li enolates of carboxylic acids are such nucleophiles for the eyclopropanation [89,90], The Li enolate of the ketone 201 reacts with tt-aUylpalladium chloride to afford the a-cyclopropyl ketone 202 in the presence of TMEDA under CO atmosphere [91]. 

The remaining new approaches to muscone all rely upon methods of ring expansion. Ferric chloride treatment of l,4-bis(trimethylsilyloxy)-bicyclo[12,l 0]pentadecane (155), obtained by cyclopropanation of the cyclotetradecene (154) with diethylzinc and methylene iodide, resulted in a one-carbon ring expansion to a muscone precursor, the dione (156). Anodic oxidation of the potassium salt of the /8-hydroxy-carboxylic acid (158), formed by Reformat-sky reaction of the enone (157), led, also by a one-carbon ring enlargement, to a mixture of the I3y- and a/8-unsaturated ketones (159) which was converted into... 

Then the carboxylic acid was converted (via the acid chloride) to the diazoketone (Chapter 9), and decomposition of the latter via the carbene and insertion produced the substituted cyclopropane. Next, the keto group was converted to a methylene unit via the Wittig, and thermolysis generated the third cyclopentyl ring. Dissolving metal reduction and epimerization in sodium ethoxide set the stage for conversion of the ester to an alkyl group. 

Even an oligopeptide has been attached to (Table 4.3, compound 130) [111]. This was achieved by a coupling reaction of the carboxylic group in the side chain of the cyclopropane ring as well. First, the tert-butylcarboxylate 129 was synthesized by the reaction of the corresponding diazomethylbenzoate with Cgg. After hydrolysis with trifluoromethanesulfonic acid, the acyl chloride was generated by treatment with oxalyl chloride. Finally, in a one-step procedure the fullerene peptide 130 was obtained by the reaction with the N-deprotected pentapeptide H-(L-Ala-Aib)2-L-Ala-OMe. 

The important commercial compound (/ )-pantolactone is formed in high yield and ee from the bis-carbamate 417 after carboxylation and lactonisation.178 Attempts to quench the organolithium with Me3SiCl failed instead the silyl chloride acted as a Lewis acid, promoting displacement of the second carbamate and leading to the cyclopropane 420.162>179 Further functionalisation of the cyclopropane was possible by stereospecific alkylation of the ring. 

Addition of methoxycarbonylnitrene generated photochemically from methyl azidoformate to methylenecyclopropane gave methyl l-azaspiro[2.2]pentane-l-carboxylate 1, which cannot be isomerized to the cyclobutane derivative like the isosteric oxaspiropentanes. " Treatment with acids such as hydrogen chloride or methanesulfonic acid cleaved the aziridine ring and gave l-(chloromethyl)-l-(methoxycarbonylamino)cyclopropane and l-(mesyloxymethyl)-l-(methoxycarbonylamino)cyclopropane. ... 

The lithium enolate derived from ethyl dithiane carboxylate reacts with aldehydes to furnish /3-hydroxy-ester derivatives in good yield. The Lewis acid-promoted additions of carbonyl compounds to donor-acceptor-substituted cyclopropanes, leads initially to /3-hydroxy-esters, which undergo subsequent conversion to chlorides or dihydrofurans (Scheme 41). "... 

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