Cyclopropanecarboxylates, synthesis

Cyclopentenones reactions of 835, 836 synthesis of 620 Cyclopropanation 648 Cyclopropanecarboxylates, synthesis of 318 Cyclopropanes, synthesis of 772, 773, 785-787... 

In contrast to the synthesis of carbocyclic rings, the Cope rearrangement has been used sparsely for generating azepinones. Recently, the enantioselectivity of the conversion of 2-aza-divinylcyclopropane 286 has been investigated. The synthesis started from the optically active cyclopropanecarboxylic acid (90% ee), which had been converted into the isocyanate 286 by initial azidation to 285 and a consecutive Curtius rearrangement. Furthermore, the conditions of the iso-... 

CYCLOPROPANECARBOXYLIC ACID, cis-2-PHENYL-, 50, 94 Cyclopropane derivatives, synthesis, 52, 22, 33, 132 Cyclopropenes, 50, 30 Cyclopropenone, di-tert-buty1-,... 

Schemes. The productive three-step synthesis of bicyclopropylidene (1) utilizing the Kulinkovich reaction of methyl cyclopropanecarboxylate [14]...

Cyclopentanes, synthesis, 66, 10 CYCLOPEKTANONE SYNTHESIS, 66, 87, 92, 93 Cyclopentanone, 2-carbomethoxy-3-vinyl, 66, 56 Cyclopentanone, 2-ethenyl-2-methyl (88729-76-4), 66, 94 2-CYCLOPENTEN-l-ONE, 3-METHYL-2-PENTYL-, 65, 26 Cyclopropane, l-trimethy1s1lyloxy-1-ethoxy-, 56, 44 Cyclopropanecarboxylic acid chloride, 66, 176... 

G. Haufe, T.C. Rosen, O.G.J. Meyer, R. Frohlich, K. Rissanen, Synthesis, reactions and structural features of monofluorinated cyclopropanecarboxylates, J. Fluor. Chem. 114 (2002) 189-198. 

Cyclopropanecarboxylic acid may be prepared by a malonic ester synthesis, as retrosynthetic analysis shows. 

Aratani, T. (1985) Catalytic asymmetric synthesis of cyclopropanecarboxylic acids an application of chiral copper carbenoid reaction. Pure Appl. Chem., 57, 1839. 

A new versatile synthesis of tert-butyl 2-alkoxy-cyclopropanecarboxylates. Synlett 1992, 735— 737. 

The 1-ADPM reaction has been used as the key step in the synthesis of a series of cyclopropanecarboxylic acids present in insecticidally-active pyrethrins and pyrethroids [63]. Thus, acetophenone-sensitized irradiation... 

Cyclopropanecarboxylic acid, 1-amino-, deuteriated, enantiospeciflc synthesis, 57, 263... 

The procedme for preparing cyclohexanecarboxyhc acid chloride is exactly the same as that described above for the preparation of cyclopropanecarboxylic acid chloride. In this case f f. 9 g (0.10 mol) of freshly distilled or reagent-grade thionyl chloride and 7.66 g (0.06 mol) of cyclohexanecarboxyhc acid are used. Cyclohexanecarboxyhc acid is a sohd that melts at 31°C, but it is easier to handle as a liquid. As an effective and safe (under normal precautions) method of melting the acid for weighing and addition to the thionyl chloride, apply steam to the exterior of the bottle or the dropping funnel. As with the previous synthesis, one may distiU this acid chloride (bp 125°C/760 Torr), or one may use it without distillation in the next step. 

S. Abele, P. Seiler, D. Seebach, Synthesis, Crystal Structures, and Modelling of P-Oligopeptides Consisting of l-(Aminomethyl)cyclopropanecarboxylic Acid Ribbon-Type Arrangement of Eight-Membered H-Bonded Rings , Helv. Chim. Acta 1999, 82, 1559 - 1571. 

The cyanoacetic ester synthesis with ethylene bromide is preferred to the malonic ester synthesis for the preparation of cyclopropanecarboxylic acid. ... 

Cyclopropanes via abnormal Hofmann elimination. This procedure provides ethyl 1-benzylcyclopropanecarboxylate in significantly improved yield and is generally applicable to the synthesis of I-substituted cyclopropanecarboxylic esters. 

In addition to the general synthetic methods mentioned in the previous sections, this section deals with specific procedures for the synthesis of cyclopropanes which entail completely different reaction mechanisms. The acid-catalysed cyclization of the 4,6,6,6-tetrachlorohexanoic acid derivative 441 gives cyclopropanecarboxylic ester (442) (equation 149) . ... 

In a similar manner, the 2-cyano-6-oxazolopiperidine synthon is useful for the chiral synthesis of in-dolizidine (monomerine piperidine [(+)- and (-)-coniine and dihydropinidine] and quinolizidine alkaloids.2-Hydroxymethyl-1-amino-1-cyclopropanecarboxylic acid (-)-(2I )-hydroxy-(3S)-nonylamine and a-substituted phenylethylamines are obtained in optically active form from (-)-N-cyanomethyl-4-phenyloxazolidine. 

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