1,2-Benzothiaborolide:  A New Heteroaromatic Analogue of Indenyl

Abstract

The reaction of 2-methylbenzenethiol with 2 equiv of BuLi followed by (i-Pr) 2 NBCl 2 affords 2,3dihydro-2-(diisopropylamino)-1,2-benzothiaborole ( 10), which can be deprotonated by t-BuLi to form lithium 2-(diisopropylamino)-1,2-benzothiaborolide ( 3). The benzothiaborolide was converted to the Cp*ZrCl 2 complex 11 and the Cp*Ru complex 12, in which the thiaborolide ring is η 5 -coordinated to Ru.

Aromatic Borataheterocycles: Surrogates for Cyclopentadienyl in Transition-Metal Complexes

“…The Cp*Ru complex of 2-(diisopropylamino)-1,2-benzothiaborolyl ( 21b ) has been prepared by a similar route (see Scheme ) . In this case the key step in construction of the boron−sulfur heterocycle was the reaction of the 1,4-dilithio compound 19 with (i-Pr) 2 NBCl 2 , which afforded 20b .…”

µ-η3:η4-Lithiocene and η3:η3-zincocene incorporating 1,2-diaza-3,5-diborolyl, a cyclopentadienyl analog

“…0.93 g (60%) of product distilled at 78 uC/5 torr as a clear colorless liquid. d H (400 MHz, C 6 D 6 , 25 uC) 0.25 (q, br, 1H, 3 J HH 5 8.2 Hz, HCCH 3 ), 0.64 (s, 6H, BCH 3 ), 1.17 (d, 12H, 3 1,2-Diaza-3,5-diborolyllithium, 2: A yellow solution containing lithium 2,2,6,6-tetramethylpiperidide, LiTMP was formed in situ from 1.6 M n-butyllithium in hexane (11.06 ml, 17.7 mmol) and 2,2,6,6-tetramethylpiperidine, TMP, (2.50 g, 17.7 mmol) in THF (3 mL). The solutions of 1 (1.14 g, 5.90 mmol) in THF (3 mL) and LiTMP were pre-cooled to 230 uC, mixed and kept at this temperature for another 2 h. The yellow solution was allowed to warm to room temperature overnight.…”

“…The product was obtained as a colorless powder (1.07 g, 90.8%). d H (400 MHz, THF-d 8 , 25 uC) 0.33 (s, 6H, BCH 3 ), 1.16 (d, 12H, 3 J HH 5 6.8 Hz, CH(CH 3 ) 2 ), 1.66 (s, 3H, CCH 3 ), 3.76 (sept, 2H, 3 Zn requires 450.3386). X-Ray crystal structure analysis of 2 and 3: Nonius Kappa CCD diffractometer, Mo Ka radiation, l 5 0.71073 A ˚, scan mode v and Q, T 5 173(2)K, Lorentz and polarization correction as well as absorption correction using multi-scan method.…”