Functional group chemistry at intramolecular frustrated Lewis pairs: substituent exchange at the Lewis acid site with 9-BBN.
نویسندگان
چکیده
The vicinal frustrated P/B Lewis pair (FLP) Mes(2)PCH(2)CH(2)B(C(6)F(5))(2) reacts with 9-borabicyclo[3.3.1]nonane (9-BBN) by C(6)F(5)vs. H exchange at boron to give the new [B]-H functionalized FLP Mes(2)PCH(2)CH(2)B(H)(C(6)F(5)) (4) and 9-C(6)F(5)-BBN. The latter was characterized as an isonitrile adduct by X-ray diffraction. The new FLP 4 forms an adduct with pyridine and it undergoes clean hydroboration reactions with 1-pentyne or added styrene or dimesitylvinylphosphane. The products formed stable adducts with pyridine; two such examples were also characterized by X-ray crystal structure analysis. A similar alkyl vs. hydrogen exchange was observed upon treatment of an Al/N based Lewis pair, iBu(2)Al-(Me(3)Si)C=C(H)-N(CH(2)CH(2))(2)NMe (14), with 9-BBN.
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ورودعنوان ژورنال:
- Dalton transactions
دوره 42 3 شماره
صفحات -
تاریخ انتشار 2013