Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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List of 1,3-hydrogen shift tautomers

formula	molecule			tautomer			type
	name	casno	sketch	name	casno	sketch
C2H2O	ethynol	32038792		Ketene	463514		CO
C2H3N	Ethynamine	52324046		Ethenimine	17619226		CN
C2H3N	Ethenimine	17619226		Acetonitrile	75058		CN
C2H3N	1H-Azirine	157175		2H-Azirine	157164		CN
C2H4O	ethenol	557755		Acetaldehyde	75070		CO
C2H4O2	1,3-dioxetane	61233190		methyl formate	107313		CC
C2H5N	ethanimine	20729413		aminoethene	593679		CN
C3H4	allene	463490		propyne	74997		CC
C3H4N2	2H-Imidazole	9000173		4H-Imidazole	9000162		CC
C3H4N2	4H-Imidazole	9000162		1H-Imidazole	288324		CN
C3H4O	allenol	9000071		Acrolein	107028		CO
C3H4O2	propanedial	542789		β–Propiolactone	57578		CC
C3H4O2	2-Propenoic acid	79107		β–Propiolactone	57578		CO
C3H4O2	propenalol	9000128		propanedial	542789		CO
C3H5	1-propenyl radical	6067681		Allyl radical	1981802		CC
C3H6O	Oxetane	503300		Propanal	123386		CC
C3H6O	2-Propen-1-ol	107186		Propylene oxide	75569		CO
C3H6O2	1,3-Dioxolane	646060		Ethyl formate	109944		CC
C4H4	Butatriene	2873509		1-Buten-3-yne	689974		CC
C4H5N	3H-pyrrole	9000366		Pyrrole	109977		CN
C4H5N	2H-pyrrole	9000377		Pyrrole	109977		CN
C4H6	1-Methylcyclopropene	3100047		1,2-Butadiene	590192		CC
C4H6	Methylenecyclopropane	6142730		1-Methylcyclopropene	3100047		CC
C4H6	Cyclobutene	822355		1,3-Butadiene	106990		CC
C4H6	1,2-Butadiene	590192		1,3-Butadiene	106990		CC
C4H6	1,2-Butadiene	590192		1-Butyne	107006		CC
C4H6	1,2-Butadiene	590192		2-Butyne	503173		CC
C4H6N	pyrrole, alpha-protonated	910095204		pyrrole, protonated	9000911		CN
C4H6O	cis-2-butenal	15798648		Furan, 2,5-dihydro-	1708298		CC
C4H6O	Furan, 2,3-dihydro-	1191997		Vinyl ether	109933		CC
C4H6O	Furan, 2,5-dihydro-	1708298		Furan, 2,3-dihydro-	1191997		CC
C4H6O2	γ–Butyrolactone	96480		2-Propenoic acid, methyl ester	96333		CC
C4H6OS	4,5-dihydrothiophene-3-ol	9000082		Dihydro-3-(2H)-thiophenone	1003049		CO
C4H6OS	2,5-dihydrothiophene-3-ol	9000093		Dihydro-3-(2H)-thiophenone	1003049		CO
C4H6OS	4,5-dihydrothiophene-2-ol	9000106		Dihydro-2-(3H)-thiophenone	1003107		CO
C4H6S	Thiophene, 2,3-dihydro-	1120598		Divinyl sulfide	627510		CC
C4H6S	Thiophene, 2,5-dihydro-	1708323		Thiophene, 2,3-dihydro-	1120598		CC
C4H7Cl	2-Butene, 2-chloro-, (Z)-	4628211		1-Butene, 3-chloro-	563520		CC
C4H7Cl	2-Butene, 2-chloro-, (Z)-	4628211		1-Butene, 2-chloro-	2211703		CC
C4H7Cl	2-Butene, 2-chloro-, (E)-	4894615		1-Butene, 3-chloro-	563520		CC
C4H7Cl	2-Butene, 2-chloro-, (E)-	4894615		1-Butene, 2-chloro-	2211703		CC
C4H7Cl	(Z)-1-Chloro-1-butene	7611861		2-Butene, 1-chloro-	591979		CC
C4H7Cl	(E)-1-Chloro-1-butene	7611872		2-Butene, 1-chloro-	591979		CC
C4H7Cl	1-Butene, 4-chloro-	927731		2-Butene, 1-chloro-	591979		CC
C4H8	2-Butene, (E)-	624646		1-Butene	106989		CC
C4H8	cyclobutane	287230		1-Butene	106989		CC
C4H8O	Furan, tetrahydro-	109999		Ethene, ethoxy-	109922		CC
C4H8O	Butanal	123728		Furan, tetrahydro-	109999		CC
C4H8O	Cyclobutanol	2919235		Butanal	123728		CO
C4H8O2	1,3-Dioxolane, 2-methyl-	497267		Ethyl acetate	141786		CC
C4H9	Isobutyl radical	4630459		Tert-butyl radical	1605738		CC
C5H10	Cyclopropane, 1,1-dimethyl-	1630940		1-Butene, 2-methyl-	563462		CC
C5H10	1-Butene, 2-methyl-	563462		2-Butene, 2-methyl-	513359		CC
C5H10	Cyclopentane	287923		1-pentene	109671		CC
C5H10	2-Pentene, (E)-	646048		1-pentene	109671		CC
C5H10O	2H-Pyran, tetrahydro-	142687		Pentanal	110623		CC
C5H10O	Pentanal	110623		Cyclopentanol	96413		CO
C5H10S	3-Ethylthio-1-propene	5296628		2H-Thiopyran, tetrahydro-	1613510		CC
C5H10S	3-Ethylthio-1-propene	5296628		Thiophene, tetrahydro-3-methyl-	4740005		CC
C5H5NO	3(6H)-Pyridinone	9000015		3(2H)-Pyridinone	9000004		CC
C5H5NO	3(4H)-Pyridinone	9000026		3(2H)-Pyridinone	9000004		CC
C5H5NO	3(4H)-Pyridinone	9000026		3(6H)-Pyridinone	9000015		CC
C5H5NO	2(3H)-Pyridinone	9000048		2(5H)-Pyridinone	9000037		CC
C5H5NO	4(1H)-Pryidinone	9000060		4(3H)-Pryidinone	9000059		CC
C5H5NO	2(1H)-Pyridinone	72762006		2(5H)-Pyridinone	9000037		CC
C5H5NO	2(1H)-Pyridinone	72762006		2(3H)-Pyridinone	9000048		CC
C5H5NO	2(1H)-Pyridinone	72762006		2-Pyridinol	109104		CO
C5H5NO	4(3H)-Pryidinone	9000059		4-Pyridinol	626642		CO
C5H5NO	2(3H)-Pyridinone	9000048		2-Pyridinol	109104		CO
C5H5NO	3(4H)-Pyridinone	9000026		3-Pyridinol	109002		CO
C5H5NO	3(2H)-Pyridinone	9000004		3-Pyridinol	109002		CO
C5H6	3-Penten-1-yne, (Z)-	1574409		1,3-Cyclopentadiene	542927		CC
C5H7	1,3-pentadienyl radical	14362084		cyclopentenyl radical	10577658		CC
C5H7N	(E)-2-Pentenenitrile	26294984		Cyclobutanecarbonitrile	4426113		CC
C5H7N	(E)-2-Pentenenitrile	26294984		(E)-3-Pentenenitrile	16529661		CC
C5H8	1,3-Pentadiene, (E)-	2004708		1,4-Pentadiene	591935		CC
C5H8	1,3-Pentadiene, (E)-	2004708		1,2-Pentadiene	591957		CC
C5H8	1,2-Butadiene, 3-methyl-	598254		1,3-Butadiene, 2-methyl-	78795		CC
C6H10	Cyclopentene, 3-methyl-	1120623		1,5-Hexadiene	592427		CC
C6H10	Cyclopentene, 3-methyl-	1120623		Cyclopentene, 1-methyl-	693890		CC
C6H10	Cyclopentene, 4-methyl-	1759815		Cyclopentene, 3-methyl-	1120623		CC
C6H10	1,4-Hexadiene, (Z)-	7318674		Cyclopentene, 4-methyl-	1759815		CC
C6H10	1,4-Hexadiene, (E)-	7319008		1,5-Hexadiene	592427		CC
C6H10	1,4-Hexadiene, (E)-	7319008		2,4-Hexadiene, (E,E)-	5194514		CC
C6H10	1,3-Hexadiene, (Z)-	14596920		Cyclopentene, 3-methyl-	1120623		CC
C6H10	1,3-Hexadiene, (E)-	20237347		1,4-Hexadiene, (E)-	7319008		CC
C6H12	3-methylenepentane	760214		(E)-3-methylpent-2-ene	616126		CC
C6H12	Ethylcyclobutane	4806615		hex-1-ene	592416		CC
C6H12	hex-1-ene	592416		Cyclopentane, methyl-	96377		CC
C6H12	hex-1-ene	592416		Cyclohexane	110827		CC
C6H12	2,3-dimethyl-but-2-ene	563791		2,3-dimethylbut-1-ene	563780		CC
C6H6O	2,4-Cyclohexadienone	24599573		2,5-Cyclohexadienone	5664335		CC
C6H6O	2,4-Cyclohexadienone	24599573		phenol	108952		CO
C6H8	1,4-Cyclohexadiene	628411		1,3-Cyclohexadiene	592574		CC
C6H8	3-Methylenecyclopentene	930267		Bicyclo[2.1.1]hex-2-ene	822413		CC
C6H8	Bicyclo[3.1.0]hex-2-ene	694019		1,3-Cyclohexadiene	592574		CC
C6H8	(Z)-hexa-1,3,5-triene	2612466		3-Methylenecyclopentene	930267		CC
C8H6	benzocyclobutadiene	4026237		phenylacetylene	536743		CC
C8H8	cyclooctatetraene	629209		Styrene	100425		CC
CH2N2	cyanamide	420042		diiminomethane	151519		NN
CH3N2	diiminomethane, protonated	9000801		Cyanamide, protonated	9000800		NN
CH3NO	nitrosomethane	865407		formaldoxime	75172		CO
CH3NO	hydroxymethylimine	9000777		formamide	75127		NO
CH4NO2	Carbamic acid, O-protonated	271587032		protonated Carbamic acid	9000833		NO
CH5N2O	urea, protonated	952102862		urea, N-protonated	9000810		NO
HN2O	Nitrous oxide, N-protonated	107190772		Nitrous Oxide, O-protonated	76412549		NO