Although a sulfur atom belongs to the same group 16 as an oxygen atom in the periodic table, it has specific properties which an oxygen atom does not. For example, the features of a sulfur atom include the following: the lone pair of a divalent sulfur atom has a soft and strong nucleophilicity but it has a weak affinity for hard acids such as a proton; the carbon-sulfur bond can be easily cleaved in various reactions; and it has a variety of atomic valences, etc. Organic sulfur compounds play important roles in organic synthetic chemistry because of the variety of their features. We introduce the following three examples of the role of sulfur compounds as reaction reagents in organic synthetic chemistry:

(1) Oxidizing agents
By the Swern oxidation and the Corey-Kim oxidization using DMSO, primary and secondary alcohols can be oxidized to aldehydes and ketones, respectively. In the Corey-Kim oxidation, dodecyl methyl sulfides (D3767) can be used to prevent the offensive odor of dimethyl sulfide.¹⁾

(2) C-C bond formation in the alpha position
When 1,3-dithiane is treated with alkyllithium, an anion is generated in the C-2 position. The alkyl halide A reacts with this to give a monoalkylated 1,3-dithiane. Furthermore, by the same treatment, alkyl halide B reacts with this to give a dialkylated 1,3-dithiane. Therefore, two units, A and B, can be combined with a methylene unit.²⁾ In addition, the dithioketal can be also obtained by protecting the ketone with 1,3-propanediol. It means that umpolung has occurred since the carbonyl carbon was originally positively-polarized.

(3) Leaving groups
Functional sulfur groups can be removed by treatment with reducing agents. Dithioketal shown in the examples above can be changed into methylene by reacting with hydrogen in the presence of the Raney-nickel catalyst. The modified Julia olefination is also known as the reductive elimination reaction of sulfones, and it is widely used for the total synthesis of natural products as a stereoselective olefin synthesis.³⁾ E/Z selectivity varies with the type of aryl sulfone to be employed. Aryl sulfone is synthesized from the corresponding arylthiol. If ArSH is 2-mercaptobenzothiazole, the reaction is E-selective, but in the case of 2-mercaptopyridine, it becomes Z-selective.

In this section, we introduced the sulfur compounds used mainly in organic synthesis as reagents. We provide the building blocks, such as thiophenes and thiazoles, which can be found by a structure or keyword search on our website.

Disulfides

Sulfides

Thiols

Sulfenic Acid Derivatives

Thiocarbonyl Compounds

Sulfoxides

Sulfinic Acid Derivatives

Sulfones

Sulfonic Acids

Sulfonic Acid Derivatives

Others (Sulfur Compounds for Synthesis)

Disulfides

D1114	D3774	B3587
S0379	B3360	D0244

D1114	2,2'-Dipyridyl Disulfide [for Peptide Synthesis]
D3774	2,2'-Dithienyl Disulfide
B3587	Bis(2-hydroxyethyl) Disulfide (ca. 50% in Water)
S0379	Bis(2-hydroxyethyl) Disulfide [Matrix for FABMS and liquid SIMS]
B3360	Bis(2-methyl-3-furyl) Disulfide
D0244	Bis(6-hydroxy-2-naphthyl) Disulfide

Sulfides

P0753	P1602	P1172
B1378	B1650	T2217
T2216	B1709	D0119
D1648	D2105	B2658
T1514	B2659	B2662
B2661	B2660	B2004
B1444	H0871	C1601
D3767	P1085	B1411
I0461	M1216

P0753	(Phenylthio)acetic Acid
P1602	(Phenylthio)acetonitrile
P1172	(Phenylthiomethyl)trimethylsilane
B1378	1,1-Bis(methylthio)-2-nitroethylene
B1650	1,1-Bis(methylthio)ethylene
T2217	1,2,4,5-Tetrakis(tert-butylthio)benzene
T2216	1,3,5-Tris(tert-butylthio)benzene
B1709	1,3-Bis(methylthio)-2-methoxypropane
D0119	1,3-Dithiane
D1648	1,3-Dithiane-2-carboxylic Acid Ethyl Ester
D2105	1,3-Dithiolane-2-carboxylic Acid Ethyl Ester
B2658	1-Bromo-3,5-bis(tert-butylthio)benzene
T1514	2-Trimethylsilyl-1,3-dithiane
B2659	3,5-Bis(tert-butylthio)-1-chlorobenzene
B2662	3,5-Bis(tert-butylthio)benzyl Acetate
B2661	3,5-Bis(tert-butylthio)benzyl Alcohol
B2660	3,5-Bis(tert-butylthio)benzyl Bromide
B2004	Bis(methylthio)(trimethylsilyl)methane
B1444	Bis(phenylthio)methane
H0871	Bis(trimethylsilyl) Sulfide
C1601	Chloromethyl p-Tolyl Sulfide
D3767	Dodecyl Methyl Sulfide
P1085	Ethyl (Phenylthio)acetate
B1411	Ethyl 3,3-Bis(methylthio)-2-cyanoacrylate
I0461	Isobutylene Sulfide
M1216	Methoxymethyl Phenyl Sulfide

Thiols

B1322	E0032	B2656
P0763	B1505	P0640
M0055	M0247	M0246
B2391	B2655	T0266

B1322	1,2-Benzenedithiol
E0032	1,2-Ethanedithiol
B2656	1,3,5-Benzenetrithiol
P0763	1,3-Propanedithiol
B1505	1,4-Benzenedithiol
P0640	1-Phenyl-5-mercapto-1H-tetrazole
M0055	2-Mercaptobenzothiazole
M0247	2-Mercaptobenzothiazole
M0246	2-Mercaptopyridine
B2391	3,5-Bis(trifluoromethyl)benzenethiol
B2655	5-Bromo-1,3-benzenedithiol
T0266	Toluene-3,4-dithiol

Sulfenic Acid Derivatives

C1043	M0979	B2240
T1237

C1043	Chlorocarbonylsulfenyl Chloride
M0979	Methoxycarbonylsulfenyl Chloride
B2240	N-tert-Butylbenzenesulfenamide
T1237	Triphenylmethanesulfenyl Chloride

Thiocarbonyl Compounds

M1473	D1944	D2113
P1236	P1056	T0635
B0479	T1555

M1473	5-(Methacryloyloxy)methyl-1,3-oxathiolane-2-thione
D1944	Dimethyldithiocarbamic Acid Allyl Ester
D2113	Dimethylthiocarbamoyl Chloride
P1236	Phenyl Chlorothionoformate
P1056	Pyrrolidinodithiocarbamic Acid Allyl Ester
T0635	Tetrabutylthiuram Disulfide
B0479	Tetraethylthiuram Disulfide
T1555	Tetraisopropylthiuram Disulfide

Sulfoxides

T2545	T2546	D0798
M0805	M1148	P1135

T2545	(R)-(p-Toluenesulfinyl)ferrocene
T2546	(S)-(p-Toluenesulfinyl)ferrocene
D0798	Dimethyl Sulfoxide
M0805	Methyl (Methylsulfinyl)methyl Sulfide
M1148	Methyl Phenyl Sulfoxide
P1135	Phenylsulfinylacetic Acid Ethyl Ester

Sulfinic Acid Derivatives

M1044	M1066	B2907
B2908

M1044	(1R,2S,5R)-(-)-Menthyl (S)-p-Toluenesulfinate
M1066	(1S,2R,5S)-(+)-Menthyl (R)-p-Toluenesulfinate
B2907	(R)-(+)-tert-Butylsulfinamide
B2908	(S)-(-)-tert-Butylsulfinamide

Sulfones

C1304	D0557	B2434
C1236	C1237	A1444
B1573	D3161	D0959
E0427	E0466	F0341
M0401	M0875	P1250
P0982	B1574

C1304	2-Chloroethyl Phenyl Sulfone
D0557	3-Sulfolene
B2434	4-Benzylthiomorpholine 1,1-Dioxide
C1236	4-Chlorophenyl Cyanomethyl Sulfone
C1237	4-Chlorophenyl Methyl Sulfone
A1444	Allyl Phenyl Sulfone
B1573	cis-1,2-Bis(phenylsulfonyl)ethylene
D3161	Di-n-octyl Sulfone
D0959	Divinyl Sulfone (stabilized with HQ)
E0427	Ethyl Phenyl Sulfone
E0466	Ethynyl p-Tolyl Sulfone
F0341	Fluoromethyl Phenyl Sulfone
M0401	Methyl Phenyl Sulfone
M0875	Methylthiomethyl p-Tolyl Sulfone
P1250	Phenyl Trimethylsilylmethyl Sulfone
P0982	Phenyl Vinyl Sulfone
B1574	trans-1,2-Bis(phenylsulfonyl)ethylene

Sulfonic Acids

B0030

B2678

T0267

B0030	Benzenesulfonic Acid Monohydrate
B2678	Benzenesulfonic Acid Monohydrate
T0267	p-Toluenesulfonic Acid Monohydrate

Sulfonic Acid Derivatives

C1324	C1325	C1326
C1327	N0604	T1562
T0459	M1186	N0576
C1142	M0071	B1931
C0886	M1182	E0471
H1176	T1461	B1389
T1471	T0272	T0998
T1046	T1185	M1382
D2390

C1324	(+)-10,2-Camphorsultam
C1325	(-)-10,2-Camphorsultam
C1326	(2R,8aS)-(+)-(Camphorylsulfonyl)oxaziridine [Asymmetric Oxidizing Reagent]
C1327	(2S,8aR)-(-)-(Camphorylsulfonyl)oxaziridine [Asymmetric Oxidizing Reagent]
N0604	1-(4-Nitrobenzenesulfonyl)-1H-1,2,4-triazole
T1562	2,4,5,6-Tetramethylbenzenedisulfonyl Dichloride
T0459	2,4,6-Triisopropylbenzenesulfonyl Chloride
M1186	2,4-Mesitylenedisulfonyl Dichloride
N0576	2-(1-Naphthyl)ethanesulfonyl Chloride
C1142	2-Chloroethanesulfonyl Chloride
M0071	2-Mesitylenesulfonyl Chloride
B1931	Benzenesulfonic Anhydride
C0886	Chlorosulfonyl Isocyanate
M1182	Ethyl O-Mesitylsulfonylacetohydroxamate [Precursor of the Powerful Aminating Reagent]
E0471	Ethylene Di(thiotosylate) [Protecting Reagent for Active Methylene]
H1176	Heptadecafluoro-n-octanesulfonyl Fluoride
T1461	N-Sulfinyl-p-toluenesulfonamide
B1389	N-[Bis(methylthio)methylene]-p-toluenesulfonamide
T1471	Octadecyl p-Toluenesulfonate
T0272	p-Toluenesulfonyl Chloride
T0998	p-Toluenesulfonyl Isocyanate
T1046	p-Toluenesulfonylmethyl Isocyanide
T1185	p-Toluenethiosulfonic Acid Potassium Salt
M1382	S-Methyl Methanethiosulfonate
D2390	Trimethylene Di(thiotosylate) [Protecting Reagent for Active Methylene]

Others (Sulfur Compounds for Synthesis)

C1380	B1151	B1376
B3125	B1517	C1159
C1390	D1945	D2231
D2159	D2685	B1133
M1083	P1254	C1122
B2188	P0998	D2078
D2114	D2002	T2136
T1308	T1564	T1833
T1065

C1380	(3-Chloropropyl)diphenylsulfonium Tetrafluoroborate
B1151	1,3-Benzodithiolylium Tetrafluoroborate [Hydroxyl-Protecting Agent]
B1376	2,4-Bis(p-tolylthio)-1,3-dithia-2,4-diphosphetane-2,4-disulfide [Sulfurating Reagent]
B3125	3H-1,2-Benzodithiol-3-one 1,1-Dioxide
B1517	Belleau's Reagent [Sulfurating Reagent]
C1159	Copper(I) Trifluoromethanethiolate
C1390	Cyclopropyldiphenylsulfonium Tetrafluoroborate
D1945	Dimethyl(methylthio)sulfonium Tetrafluoroborate
D2231	Dimethylphenacylsulfonium Tetrafluoroborate
D2159	Dimethylthiophosphinoyl Chloride
D2685	Diphenyl(methyl)sulfonium Tetrafluoroborate
B1133	Lawesson's Reagent [Sulfurating Reagent]
M1083	Methylsulfamic Acid
P1254	N-(Phenylthio)phthalimide
C1122	N-Cyano-N',S-dimethylisothiourea
B2188	N-tert-Butylbenzenesulfinimidoyl Chloride [Oxidizing Reagent]
P0998	Pyridine - Sulfur Trioxide Complex
D2078	S,S'-Diethyl Dithiocarbonate
D2114	S,S'-Dimethyl Dithiocarbonate
D2002	S,S-Diphenylsulfilimine Monohydrate
T2136	Sulfur Trioxide - Triethylamine Complex
T1308	Tetramethyldiphosphine Disulfide
T1564	Tributylsulfonium Iodide
T1833	Trimethylsulfoxonium Bromide
T1065	Trimethylsulfoxonium Iodide