TY - JOUR
T1 - Selective Formation of Five-Membered Heterocyclic Products by Anodic Oxidation of Alkyl Isothiocyanates (RNCS)in Dichloromethane and Their Thermal Isomerization and Decomposition
AU - Becker, James Y.
AU - Yatziv, Shimon
PY - 1988/4/1
Y1 - 1988/4/1
N2 - Anodic oxidation of primary and secondary alkyl isothiocyanates (RNCS) in dichloromethane yielded two isomers of five-membered heterocyclic products, 4-alkyl-5-(alkylimino)-1,2,4-dithiazolidine-3-one 2 and 2,4-dialkyl-5-oxo-l,2,4-thiadiazolidine-3-thione 3. Their relative ratio was found to be dependent on the length or bulkiness of the alkyl group in RNCS. Isomer 2 was favorable for R = Me and Et and exclusive for R = n-Pr, n-Bu, and cyclohexyl. Upon GLC injection (at 150–200 °C), compounds of type 2 isomerized completely to 3 (when R = Me, Et), mostly to 3 and partially decomposed to RN=C=NR (11) (when R = n-Pr, n-Bu), and exclusively decomposed to 11 for R = cyclohexyl. Tertiary RNCS did not yield cyclic products but instead underwent chlorination to substitute a hydrogen (or “NCS” group) by chlorine. Plausible mechanistic schemes are suggested and discussed.
AB - Anodic oxidation of primary and secondary alkyl isothiocyanates (RNCS) in dichloromethane yielded two isomers of five-membered heterocyclic products, 4-alkyl-5-(alkylimino)-1,2,4-dithiazolidine-3-one 2 and 2,4-dialkyl-5-oxo-l,2,4-thiadiazolidine-3-thione 3. Their relative ratio was found to be dependent on the length or bulkiness of the alkyl group in RNCS. Isomer 2 was favorable for R = Me and Et and exclusive for R = n-Pr, n-Bu, and cyclohexyl. Upon GLC injection (at 150–200 °C), compounds of type 2 isomerized completely to 3 (when R = Me, Et), mostly to 3 and partially decomposed to RN=C=NR (11) (when R = n-Pr, n-Bu), and exclusively decomposed to 11 for R = cyclohexyl. Tertiary RNCS did not yield cyclic products but instead underwent chlorination to substitute a hydrogen (or “NCS” group) by chlorine. Plausible mechanistic schemes are suggested and discussed.
UR - http://www.scopus.com/inward/record.url?scp=33845279814&partnerID=8YFLogxK
U2 - 10.1021/jo00243a028
DO - 10.1021/jo00243a028
M3 - Article
AN - SCOPUS:33845279814
SN - 0022-3263
VL - 53
SP - 1744
EP - 1748
JO - Journal of Organic Chemistry
JF - Journal of Organic Chemistry
IS - 8
ER -