> Dear Dr Mario R.Tellez:
>
> I have read your interesting poster about the conversion of the
> thiazetidinone into carbodiimide or isourea derivatives.
> I am working in the synthesis of bis(carbodiimides) as intermediates in the
> preparation of 1,3-diazetidine-1,4-diimines (poster n. 073), and I would
> like to know the experimental details to achieve the conversion of
> N,N'-bis(4-fluorophenyl)thiourea (5) in
> 3-(4-fluorophenyl)-1,3-thiazetidin-4-one-2-(4-fluorophenyl)imine (4)
> (Scheme 6).
>
> Thanks in advance.
>
> Pilar Sanchez Andrada
> Departamento de Quimica Organica
> =46acultad de Quimica
> Universidad de Murcia
> Spain
>
>
> -----
> ECHET96. Conference home page: http://www.ch.ic.ac.uk/ectoc/echet96/ using
> Netscape, Mosaic, etc.
> E-mail discussions: http://www.ch.ic.ac.uk/hypermail/echet96/
> To unsubscribe from this list, send the message UNSUBSCRIBE ECHET96 to
> listserver@ic.ac.uk
>
>
>
Pilar:
Here is the info you asked me for. I am in the process of reading
your poster and am finding it very interesting.
To N,N'-bis(4-fluorophenyl)-thiourea (1.32 g, 5 mmoles) in
dichloromethane (25 mL) in an open 250 mL round bottom flask in an ice
bath was added triphosgene [bis(trichloromethyl)carbonate] (355 mg,
1.667mmoles) in dichloromethane (25 mL) via a pippette.The mixture was
stirred for 10 minutes in the ice bath and then overnight at room
temperature. The solid (remaining starting material) was filtered off,
and the yellow filtrate brought to reflux for one hour. The solvent was
removed under reduced pressure to afford a yellow solid. Dissolving in
acetone and adding water precipitated the product as a white solid in
63.4% yield (919 mg, 3.168 mmoles) m.p. 93.5-95.0oC. 1H NMR(CDCl3)d
7.92-7.85 (m, 2H), 7.16-7.07 (m, 6H); IR(KBr) 3018, 1812, 1670, 1504,
1225, 788; Anal. Calcd. for C14H8F2N2OS: C,57.93; H,2.78; N,9.65%. Found:
C,57.57; H,2.99; N,9.52%.
Hope this helps. I also have GC-MS and C13 info on the product if you
should be interested. Let me know if you need any added info.
Good luck.
Mario.
-----
ECHET96. Conference home page: http://www.ch.ic.ac.uk/ectoc/echet96/ using
Netscape, Mosaic, etc.
E-mail discussions: http://www.ch.ic.ac.uk/hypermail/echet96/
To unsubscribe from this list, send the message UNSUBSCRIBE ECHET96 to
listserver@ic.ac.uk