(Dimethylamino)bis(trifluoromethyl)borane,
(CF3)2BNMe2 (1),
combines with N-sulfinylsulfonamides RO2SNSO in a [2 + 2] fashion
(R = Me (2a), Et (2b), iPr
(2c), Ph (2d), and pTol
(2e)). Aminoiminophosphines
RNPNR2‘
react with 1 analogously to yield the
= SiMe3,
NR2‘ = N(SiMe3)2 (3a),
TMP (3b); R = tBu, NR2‘ =
N(SiMe3)tBu (3c),
NiPr2 (3d), TMP
(3e)).
Carbodiimides RNCNR add to the BN bond of
1 to give unstable
which rearrange at 20 °C to
yield the four-membered heterocycles
= iPr (5a),
cC6H11 (5b)). For
carbodiimides with aryl
substituents R = pXC6H4, this
rearrangement competes with an internal electrophilic
aromatic substitution reaction and mixtures of the two
(X = H (5c), Me
(5d), OMe (5e))
(X = H (6c), Me
(6d), OMe (6e)) are obtained.
PhNCCMe2 combines with 1
to
form the four-membered
F3C−CH2−NSO
undergoes an ene-type reaction with 1 by which the
dimethylamine borane (F3CHCNS(O))(CF3)2B·NHMe2
(9) is formed. The constitution of the novel boron
compounds has been
deduced from multinuclear NMR, IR, and mass spectra. The
structures of 2a, 3c, 5c,
6d,
6e, and 8 have been investigated by
single-crystal X-ray diffraction.
1,1‐Dimethyl‐2,2‐bis(trifluoromethyl)azoniaboratacyclopropanes, cyclo‐(F3C)2B–CR1R2–NMe2 [R1 = R2 = C6H5 (2a); R1/R2 = C12H8 (2b); R1 = H, R2 = C6H5 (2c), 4‐FC6H4 (2d), 3‐FC6H4 (2e), 2‐FC6H4 (2f), C6F5 (2g), iPr (2h), tBu (2i); R1 = Me, R2 = C(=O)OMe (2j), C(=O)OEt (2k)] have been obtained from (F3C)2BNMe2 (1) and diazomethanes R1R2CN2. In contrast to compound 2a, the B–N bonds of 2b–2k hydrolyze to form the zwitterionic species Me2NH–CR1R2–B(CF3)2OH (3b–3k). The diazoacetic acid esters HC(N2)C(=O)OMe and HC(N2)C(=O)OtBu react with 1 to form three‐membered rings, which hydrolyze rapidly to form Me2NH–CR1R2–B(CF3)2OH [R1 = H, R2 = C(=O)OMe (3l), C(=O)OtBu (3m)]. F3CSiF3 reacts under elimination of CF2 with 1 to form the acyclic derivative (F3C)2BF–CF=NMe2 (4). The structures of 2a and 3ghave been investigated crystallographically. A nearly eclipsed conformation is found for the central B–C bond of 3g, which is 0.097(7) Å longer than the B–C bond length in the three‐membered ring of 2a.
CF 3 ) 2 BNMe 2 (1) reacts at room temperature with water in a 2:1 ratio to form bis(dimethylamine)-tetrakis(trifluoromethyl)diboroxane Me 2 HN·(CF 3 ) 2 BOB(CF 3 ) 2 ·NHMe 2 (2), whereas a 1:1 ratio at Ϫ78°C had yielded HO(CF 3 ) 2 B·NHMe 2 (3). The constitution of 2 has been deduced from multinuclear NMR, IR and
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.