395. Boron–nitrogen compounds. Part XI. The reaction of some boron–nitrogen compounds with organic isocyanates

Abstract

Aminoboranes added across the N=C linkage of organic isocyanates and isothiocyanates to yield N-boronated urea derivatives ; hydrolysis studies substantiate suggested structures.THE easy preparation of isocyanate and isothiocyanate derivatives of boron compounds from the corresponding boron halides and a salt of cyanic or thiocyanic acid has recently been reported.2 The reaction of organic isocyanates and isothiocyanates with boron compounds has not been so well explored; a patent claims the formation of thermally stable polymers from an organoboric acid and bifunctional isocyanates through the elimination of carbon dioxide: but these results could not be ~onfirmed.~ Boric acid condenses with phenyl isocyanate in the presence of triethylamine to form trisphenylaminoborane.5 The copolymerization of B-trisubstituted borazines with hexamethylene di-isocyanate to yield polymers (I), has been described; this reaction would indicate a relatively high reactivity of the NH groups in borazines. However, when tri-B-methylborazine was treated with acetyl chloride no reaction was observed below Boone

Facile and convenient synthesis of B‐amino‐9‐borabicyclo[3.3.1]nonanes. Aminoboration of lsocyanates

“…Calcd. for C16H25N302: C, 66.0; H,8.6;N,14.4. Found: C,66.1;H,8.6;N,14.2. Reactioii of B-Pheiiylamiiio-9-BBN with Pheiiyl Isocyaiiate iii 1:2 Molar Ratio This reaction was carried out, as described above, using phenyl isocyanate (25 mmol) and the aminoborane (10 mmol).…”

“…for C16H25N302: C, 66.0; H,8.6;N,14.4. Found: C,66.1;H,8.6;N,14.2. Reactioii of B-Pheiiylamiiio-9-BBN with Pheiiyl Isocyaiiate iii 1:2 Molar Ratio This reaction was carried out, as described above, using phenyl isocyanate (25 mmol) and the aminoborane (10 mmol). The solid adduct was collected by centrifugation, washed with n-pentane (2 X 10 mL), and dried to afford the intermediate (1, R' = Ph) (4.0g, 90 %) ; mp 123-1 25°C (acetone) : IR (KBr) urnax 3200, 2840, 1680, 1595, and 1560 cm-'; 'H NMR (acetone-d6) 6 1.0 -1.9 (m, 14 H), 3.2 (q, 3 H), 7.3 ( s , 5 H), 7.4 ( s , 5 H), 7.6 ( s , 5 H); 'lB NMR (THF) 6 + 11.6 (br s).…”