Aryl isoselenocyanates

The first route described to nonfused selenazepanes 67 from the aryl isoselenocyanates 65 and the chloro amine 66 by a stepwise amine addition-ring cyclization strategy (Equation 15) <2005TL6723> also has potential for application to the 1,3-thiazepane and 1,3-oxazepane analogues from the corresponding aryl isothiocyanates and aryl isocyanates. 

Aryl isoselenocyanates 4-RC6H4NCSe (R=H, Br, Cl, MeO) (prepared by selenation and dehydration of A-arylformamides) undergo regioselective cycloaddition reactions with 4-diethylamino-3-butyn-2-one in refluxing THF yielding W-arylselenetimines 11 (Scheme 9) <2004H(62)521>. 

Selenazolopyridines 96 are obtained by using isoselenocyanates. <2003H(61)569> Heating a solution of aryl isoselenocyanates and 3-amino-2-chloropyridine in 2-propanol under reflux leads to the formation of 2-arylamino-selenazolo[5,4-7]pyridine hydrochlorides 95, the free bases 96 being liberated with aqueous NaOH (Scheme 23). 

Selenazolines and selenazolidines of type (74) and (75) were prepared by condensing the corresponding benzyl or aryl isoselenocyanates with appropriate aminoacetylenes RR C(NHR )C=CH. ... 

A similar approach utilizing the reaction of aryl isoselenocyanates (220), the salt of a primary amine such as benzylamine, formaldehyde, and sodium hydrogen selenide yields tetrahydro-1,3,5-selenadiazine-2-selones (221) (Equation (52)) <82MI 624-01 >. 

Glucofurano-imidazoline-2-selenones such as 23 were obtained on condensation of 2-amino-2-deoxy-D-glucose with aryl isoselenocyanates. ... 

In a similar manner, aryl isoselenocyanates react with 36 to give the four-membered ring cycloadducts in moderate yields resulting from addition across the C=Se bond. ... 

The similar reaction of diethyl azodicarboxylate at room temperature with aryl isoselenocyanates in the presence of triphenylphosphine affords 4,5-dihydro-5-selenoxy-l//-1,2,4-... 

The imino heterocycle 55 reacts with benzoyl isoselenocyanate via a [2+2] cycloaddition sequence to give aryl-(4-seleno-4//-pyrido[l,2-a]pyrazin-3-yl)amines 56... 

Benzopentathiepin reacts with isothiocyanates and isoselenocyanates in the presence of triethylamine by insertion into the S-S bond. The insertion of isothuocyanates into Fe-N bonds is also observed and aryl isothiocyanates insert into unsupported Zr-M (M = Fe, Ru) bonds . 

---