Oxycarbonyl chlorides

LA Carpino, BJ Cohen, KE Stephens, SY Sadat-Aalaee, J-H Tien, DC Lakgridge. (9-Fluorenylmethyl)oxycarbonyl (Fmoc) amino acid chlorides. Synthesis, characterization, and application to the rapid synthesis of short peptide segments. J Org Chem 51, 3732, 1986... 

After ARCO patents issued, Stille and coworkers published on butadiene oxycarbonylation(14-16). Palladium was utilized as the oxidative carbonylation catalyst and copper(II) chloride was employed as a stoichiometric reoxidation agent for palladium. Although the desired hex-3 -enedioate is the exclusive product, commercial technology which uses stoichiometric copper is not practical. Once the copper(Il) is consumed, the monoatomic palladium spent catalyst agglomerates affording polymeric palladium which is not easily reoxidized to an active form. 

Pi-A -chloro-di- -(dimethyl hex-2 endioate) di-palladium is the preferred palladium catalyst and was used in the pilot plant studies outlined in Table II. Synthesis is easily accomplished by reaction of dimethyl hex- -endioate with palladium chloride. In actual butadiene oxycarbonylation runs catalyzed... 

The N-benzoyl methyl ester of Gly has been analysed on QF-1 [242] and N-benzyl-oxycarbonyl methyl and ethyl esters and N-palmitoyl ethyl esters of Leu on SE-30 [243]. N-Propionyl isoamyl derivatives of fourteen amino acids were prepared by allowing isoamyl esters to react with propionyl chloride and were also analysed on QF-1 and applied to the analysis of amino acids in bacterial cultures [244]. 

Trimethylsilyl chloride also gives the N -product alone in simple models, but this is probably the consequence of thermodynamic control in any event N -trialkylsilyl derivatives are much too labile to be useful as stepping stones to N"-alkylhistidines. The only thoroughly studied example of exclusive mono-N -derivatization is the reaction of acetic anhydride with acylhistidine esters, when thermodynamic control appears to operate. Thus, N -(benzyl-oxycarbonyl)histidine methyl ester gives only the M-acetyl derivative, providing a third kind of intermediate which is useful for N"-alkylation with reactive halides (see Section 2.6.2.3).1 1... 

Table 2 Dipeptides Synthesized Using the 1,2,3-Benzotriazol-l-yloxypotassium/A -9-Fluorenylmeth-oxycarbonyl Amino Add Chloride Method l...

Carbamyl 1,2 and oxycarbonyl 5 chlorides have proven effective starter species although their cyclization-anion capture processes have been only briefly explored (Scheme 5.6.1)." The terminating species in Scheme 5.6.1 are alkynyl (1,5) and alkenyl (3) with pre-formed Sn(IV) capmre agents. These processes, as expected, are regio-and stereoselective and their full potential remains to be explored, but reference to Table 5.6.1 indicates the substantial leverage available from alternative terminating and anion capture species. 

Peptide synthesis, N-protection Acetic-formic anhydride. Adamantyl chloroformate. Benzylthiocarbonyl chloride. /-Butoxycarbonyl-N-hydroxysuccinimide ester. /-Butyl azido-formate. /-Butylcarbonic diethylphosphoric anhydride. /-Butyl fluoroformate. /-Butyl oxycarbonyl fluoride. /-Butyl pentachlorophenyl carbonate. /-Butyl 2,4,5-trichlorophenyl carbonate. Carbobenzoxy chloride. 3,5-Dimethoxybenzyl p-nitrophenyl carbonate. [2-(Diphenyl)isopropyljphenyl carbonate. /-Pentyl chloroformate. 

C,C-Mehifachbindung-Systeme konnen sich auch an 1,3-Thiazole addicrcn, ohne daB ein zusatzlicher Ring gebildet wird. So entstehen aus 3-Ethoxycarbonyl-l,3-thiazolium-chlorid und O-Silyl-enolen 3-Eth-oxycarbonyl-2-(2-oxo-alkyl)-2,3-dihydro-l,3-thiazole (18-84%)984... 

The action of phosgene or thionyl chloride on the )V-(benzyl-oxycarbonyl)amino-acids PhCH202CNHCHRC02H (R == PhCH2 or Pr ) yields 2-oxazolin-5-ones (522), contrary to a previous report/ Numerous 3-oxazolin-5-ones (523 R , R R = alkyl or Ph) have been prepared from hydroxylamino-acids H0NHCHR C02H and ketones R COR. The revised structure (524) has been established by X-ray diffraction for the product of the reaction of ethyl diazoacetate with di-isopropylcarbodi-imide, catalysed by salts of transition metals. Treatment of the diazomethylphosphoryl compound (Me0)2P(0)CHN2 with aroyl isocyanates affords the 2-oxazolin-4-ones (525)/ ... 

Condensation of 3,4,6-tri-O-acetyl-0 -D-glucosaminyl chloride with A -(benzyl-oxycarbonyl) derivatives of L-Ser-Gly ethyl ester, L-Ser-Ala methyl ester, L-Ser-Phe methyl ester, and L-Ser-Asp dibenzyl ether gave the j3-glycosyl dipeptides... 

Another useful chain reaction involves the PTOC (pyridine-2-thione-N-oxycarbonyl) esters developed by Barton. Reaction of a carboxylic acid chloride (RCOCl) with the sodium salt on N-hydroxypyridine-2-thione produces an ester designated as R-PTOC. Addition of radical Y" (formed by an earUer initiation step) to the R-PTOC leads to the carboxy radical RCOj. The carboxy radical then decarboxylates to produce the radical R, which can continue the chain reaction or can undergo other reactions. 

Equimolar amounts of benzyloxycarbonyl-L-phenylalanine, ethyl glycinate, mercuric chloride, di-o-nitrophenyl disulfide, triphenylphosphine, and 2 moles tri-ethylamine in methylene chloride mixed 3 hrs. at room temp. ethyl benzyl-oxycarbonyl-L-phenylalanylglycinate. Y 89%. Also related condensation of sulfen-amides and cupric carboxylates s. T. Mukaiyama et al.. Am. Soc. 90, 4490 (1968). 

Bell, R.P. Lindars, F.J. Kinetics of the acid and alkaline hydrolysis of eth-oxycarbonyl-ethyltriethylammonium chloride. J. Chem. Soc. 1954, 1087-1098. Lindstedt, M. Allenmark, S. Thompson, R.A. Edebo, L. Antimicrobial activity of betaine esters, quaternary ammonium amphiphiles which spontaneously hydrolyze into nontoxic components. Antimicrob. Agents Chemother. 1990, 34, 1949-1954. 

The enhanced nucleophilicity of coordinated CO2 in complex [Fe(C02)(depe)2] allowed reaction with organotin chlorides. In the resulting carboxylate complexes 31, the CO2 unit links the two metals via a fi-ij C) if(P,0 ) bonding mode. Although the X-ray data of 31b exclude the contribution of a carbenoid form in the solid state, chemical shifts of IX-CO2 in the NMR spectra indicate a borderline case between oxycarbonyl and dioxycarbene character... 

CA Index Name Xanthylium, 3,6-diamino-9-[2-(meth-oxycarbonyl)phenyl]-, chloride (1 1)... 

The palladium(II)-catalyzed olefin carbonylation reaction was first reported more than 30 years ago in studies by Stille and co-workers and James et al. The reaction of carbon monoxide with cis- and tra 5-but-2-ene in methanol in the presence of palladium(II)-chloride and copper(II)-chloride yielded threo- and eryt/zro-3-methoxy-2-methyl-butanoate, respectively. The transformation that was based on the well-known Wacker process for oxidation of ethylene into acetaldehyde in water " is now broadly defined as the Pd(II)-catalyzed oxycarbonylation of the unsaturated carbon-carbon bonds. This domino reaction includes oxypalladation of alkenes, migratory insertion of carbon monoxide, and alkoxylation. Since the development of this process, several transformations mediated by palladium(II) compounds have been described. The direct oxidative bisfunctionalization of alkenes represents a powerful transformation in the field of chemical synthesis. Palladium(II)-promoted carbonylation of alkenes in the presence of water/alcohol may lead to alkyl carboxylic acids (hydrocarboxylation), diesters [bis(aIkoxycarbonyla-tion)], (3-alkoxy carboxylic acids (alkoxy-carboxylation), or (3-alkoxy esters (alkoxy-carbonylation or alkoxy-alkoxy-carbonylation). Particularly attractive features of these multitransformation processes include the following ... 

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