Methyl cyanodithioformate

Reactions of the sulfonylsulfines 56 (e.g. R1 = R2 = Bn R1 — Me, R2 — Ph R1 — CPh3, R2 = ph etc.) derived from (S)-proline with 2,3-dimethyl-l,3-butadiene afford dihy-drothiopyran S-oxides 57 with asymmetric induction of up to 40% (equation 38)34. Methyl cyanodithioformate 58 is a very reactive dienophile with cyclopentadiene it forms a mixture of 40 parts of the endo-adduct 59 and 60 parts of the exo-isomer 60 (equation 39)35. 

Cycloaddition reaction of the l-acyl-l,2-dihydropyridine derivative 240 with methyl cyanodithioformate afforded adduct 241, which was converted by three steps to solenopsin A (Id) (Scheme 13) (399). This route constitutes a completely stereoselective synthesis of this alkaloid however, details are not available. 

For synthetic purposes very reactive enophiles have been generally used. Methyl cyanodithioformate (1), A.A -ditosyl sulfurdiimide (2) and N-sulfinyl benzenesulfonamide (3) are but a few examples. 

A few examples of cycloadditions with the thiophosgene equivalent (189) have been reported (equation 94). In addition, methyl cyanodithioformate (190) has also been utilized several times as a heterodienophile (equation 95). ... 

Formation of a functionalized C-C bond in an allylic position can be carried out with methyl cyanodithioformate via a sequence of an ene reaction followed by a [2,3]-sigmatropic rearrangement. 2... 

Treatment of the triazolium imide dipoles 2 with methyl cyanodithioformate in benzene gives, in a particularly facile reaction, the trisubstituted thiatriazines 3 in high yield (Method A).5,8... 

Methyl cyanodithioformate (379 mg, 3.34 mmol) in anhyd benzene (50 mL) was added to 1,2-diphenyl-l,2-bis(phenyldiazenyl)ethene (1.26 g. 3.34 mmol) (which reacts as 2a) and the solution was stirred at rtfor 1 h. It was then evaporated at reduced pressure and the residue was stirred with cold EtOH to give crystals of 3a, which were collected and recrystallized (MeOH) yield 0.85 g (84%) mp 111 — 113 °C. 

Vyas and Hay reported that methyl cyanodithioformate (15) will function as a dienophile (Scheme 5-XV).41 Addition of 15 to cyclopentadiene gave a quantitative yield of exo and endo adducts in a 40 60 ratio. When 1-methoxybutadiene was used, dihydrothiapyran 16 was the major reaction product along with traces (<20%) of regioisomer 17 which was not characterized fully. The endo-cymo stereochemistry was established for 16 by extensive NMR studies. An interesting point here is that the regio-chemistry of the major product of addition of 1-methoxybutadiene and 15 is like that found with some types of thioesters (Scheme 5-VIII) and thioimides (Scheme 5-XII). Similarly, cyanothioformamides of type 18... 

Methyl cyanodithioformate. Oxygen, singlet 4-Phenyl-l,2,4-tiiazoline-3,5-dione. EPOXIDATION Biacetyl. r-Butyl hydroperoxide. /-Butyl hydiopcroxlde-Vanadyl acetyl-acctatc. m-Chloroperbenzoic acid. Iodine. Sodium hypochlorite. 

Leug et al. [24,25] reported the effects of palladium or platinum metal templates of (l-(dimelhylamino)ethyl)naphthalene on asymmetric Diels-Alder reactions of 2-diphenylphospliinofuran with diphenylvinylphosphine and of l-phenyl-3,4-dimethlylphosphole with methyl cyanodithioformate. These are shown in Eqs. (8.6) and (8.7), respectively. 

Several novel monosaccharide derivatives containing a sulphur atom in the ring have been obtained via Diels-Alder reactions of methyl cyanodithioformate with buta-1,3-diene (197) and /m/7J-l-methoxybuta-l,3-diene (198) (Scheme 73) the... 

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