Ethyl thioacetate, hydrolysis

Crystalline aldehydo-D-ribose tetraacetate (XXXII) has been prepared through the Rosenmund reduction of tetraacetyl-D-ribonyl chloride (XXXI),101 through the selective hydrolysis of tetraacetyl-D-ribose diethyl thioacetal (XXX)109 and through the Raney nickel hydrogenolysis of ethyl thiol-D-ribonate tetraacetate (XXXIII).103-104 The substance has been used in the synthesis of 2,3,4,5-tetraacetyl-D-ribitoll0B and in the synthesis of ribitylaminobenzenes.108... 

The cesium salt of thioacetic acid undergoes clean Sn2 substitution with 156b to afford (/ )-2-acetylthiopropionic acid ethyl ester (168) in nearly quantitative yield and with 100% ee [63]. Acid hydrolysis furnishes ethyl (7 )-2-mercaptopropionate (169) (92% ee). 

The 1,3-dithiane anion can be prepared in two steps from the corresponding aldehyde (formation of thioacetal, followed by deprotonation). Another option is to start with formaldehyde. Alkylation of its 1,3-dithiane anion will introduce the required ethyl group. This method can be used to prepare a variety of 13-dithiane compounds, and can even be used to synthesize aldehydes and ketones (one or two alkylation steps, followed by hydrolysis). 

Synthesis of Acetyl Ethyl Disulfides. S- Ethyl ethanethiosulfinate can be rapidly converted to acetyl ethyl disulfide In moderate yield by reaction with thioacetic acid (eq 10). Advantageously, the liberated ethylsulfenic acid can regenerate the thiosulfinate via dehydration. Acetyl ethyl disulfide is a key intermediate for the synthesis of the ethyl hydrodisulfides, which can be prepared by acid catalyzed hydrolysis. 

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