Ethyl l,3-dithiane-2-carboxylate

Ethyl l,3-dithiane-2-carboxylate [20462-00-4] M 192.3, b 75-77 /0.2mm, 96 /0.4mm, dj 1.220, n 1.5379. Dissolve in CHCI3, wash with aqueous K2CO3, 2 x with H2O, dry over MgS04, filter, evaporate and distil. [Eliel and Hartman J Org Chem 37 505 I972 Seebach Synthesis 1 17 1969.]... 

C-Alkylation of ethyl l,3-dithiane-2-carboxylate (for preparation, see 4.1.6) under mild soliddiquid phase-transfer catalytic conditions [32, 33] provides a potentially useful route to a-ketoesters. 

Ethyl diazoacetate, 228-230,325 Ethyl diethoxyacetate, 230 Ethyldiisopropylamine, 230,368 Ethyl (3,0-dimethylacrylate, 249 l-Ethyl-3-(3 -dunethylaminopropyl)carbo-diimide hydrochloride, 26 Ethyl l,3-dithiane-2-carboxylate, 230-231 Ethylene, 11 Ethylene carbonate, 41 Ethylenediamine, 231,488 Ethylenediaminetetraacetic acid, 204 Ethylenediaminetetraacetic add disodium salt, 321... 

Halogenation of 106 with triphenylphosphine, iodine, and imidazole provided the iodo derivative 109. On treatment with lithium aluminum hydride, 109 was converted into two endocyclic alkenes, 110 and di-O-isopro-pylidenecyclohexanetetrol, in the ratio of 2 1. Oxidation of 110 with dimethyl sulfoxide - oxalyl chloride afforded the enone 111.1,4-Addition of ethyl 2-lithio-l,3-dithiane-2-carboxylate provided compound 112. Reduction of 112 with lithium aluminum hydride, and shortening of the side-chain, gave compound 113, which was converted into 114 by deprotection. ... 

Stereoselective addition of a dithiane anion to chiral 2-methyl-3-trimethylsilyl-3-buterud combined with the stereoselective addition of a Grignard reagent to the chi a-alkoxy ketone affords a practical method for the construction of a,y-dimethyl-a,3-dihydroxy compounds, useful intermediates for the synthesis of erythronolides (Scheme 33). -Hydroxy cartmxylic esters were synthesized by the addition of ethyl l,3-dithiolanyl-2-carboxylate enolate to a chiral aldehyde, followed by desulfurization. ... 

Ethyl acetoacetate, 256, 257, 467, 507 Ethyl 2-alkyl-l, 3-dithiane-2-carboxylates, 230,231... 

Butyllithium in hexane injected through a septum cap at -78° under Ng during 25 min. into a soln. of 2-phenyl-l,3-dithiane in tetrahydrofuran, stirred 2 hrs. at the same temp., dimethyl disulfide injected during 10 min., allowed to warm to 25°, then poured into dil. HCl crude 2-methylthio-2-phenyl-l,3-dithiane (Y 94.5%) refluxed 4.5 hrs. under N2 with 95%-ethanol, HgClg, and HgO ethyl benzoate (Y 92.4%). F. e. and process, also carboxylic acids, s. R. A. Ellison, W. D. Woessner, and C. C. Williams, J. Org. Chem. 37, 2757 (1972). 

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