The Organometallic Alkylidene Reaction

Promoting the Hydrosilylation of Benzaldehyde by Using a Dicationic Antimony‐Based Lewis Acid: Evidence for the Double Electrophilic Activation of the Carbonyl Substrate

“…Salt [ 1 ][BF 4 ] 2 is stable over prolonged periods of time and showed no tendency towards decomposition by fluoride transfer from the BF 4 − anion to the Lewis acidic antimony center. For comparison, we also prepared the monofunctional model compound [Ph 3 MeSb][OTf] and [Ph 3 MeSb][BF 4 ], which have both been previously described.…”

“…This consideration led us to target the orthophenylene derivative [1] 2 + ,w hich features two Lewisa cidic antimony sites predisposedt oi nteract withi ncoming nucleophiles. Distibonium salts [1][OTf] 2 and [1][BF 4 ] 2 could be conveniently generated by treatment of o-phenylene-bis(diphenylstibine) [10] [11] and [Ph 3 MeSb][BF 4 ], [12] which have both been previously described.…”

Exchange reaction of oxiranes with β-hydroxyalkyl sulfides, selenides,-amines, and-phosphines

“…This type of decomposition is also known for analogous compounds of nitrogen 38 and arsenic. 49 For the reaction of ({3-hydroxyethyl)diphenylphosphine with oxiranes, the ratio of the rates of accumulation of ethylene oxide and ethylene in the reaction mixture (WI/W 2) was found; this value was defined as the ratio of the yields of these products during the first hour of the reaction. This ratio was found to increase in the following series of the oxirane substituents Rt: Me (0.07), PhOCH2 (0.50), Ph (I.50), CH2=CH (20).…”

Studies on Betaine Decomposition of Arsonium Ylides

“…The betaine decomposition pattern of non-stabilized [10,11] and stabilized ylides [1,4] has been well established but the behaviour of semistabilized arsonium ylides is quite ambivalent and this rather has been a point of controversy among so many workers from time to time. The exact course of decomposition of such betaine has been dictated by Trippett et al [4], which states that betaines formed by semistabilized arsonium ylides and carbonyl compounds either follow path (a) to give olefins or path (b) to give epoxides but not both in the same reaction mixture (Scheme 1).…”