109583-34-8Relevant articles and documents
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Brown,H.C.,Ravindranathan,M.
, p. 1865 - 1869 (1978)
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Double acylation of alkenes with acylchromates promoted by cationic Pd(II) complex
Yamane, Motoki,Ishibashi, Yuichiro,Sakurai, Hidehiro,Narasaka, Koichi
, p. 174 - 175 (2007/10/03)
Double acylation of alkenes such as norbornene and vinyl-silane proceeds by the use of acylchromate complexes and a cationic Pd(II) complex. When two different acylchromates are added successively to a mixture of alkene and the Pd complex, unsymmetrical diketones are obtained almost selectively.
Hydroboration. 87. Controlled and Sequential Hydroboration of Simple Representative Alkenes with Methylborane in Tetrahydrofuran. An Examination of the Directive Effects in the First and Second Stages of Hydroboration
Srebnik, Morris,Cole, Thomas E.,Brown, Herbert C.
, p. 5051 - 5058 (2007/10/02)
Methylborane (MeBH2), the simplest of the monoalkylboranes, possesses extraordinary hydroborating characteristics in tetrahydrofuran.In this solvent MeBH2 selectively hydroborates all important classes of alkenes, hindered and nonhindered, to yield the methylalkylboranes MeRBH.These dialkylboranes are readily converted into and isolated as their borinic esters, MeRBOR', which in turn can be transformed into methyl ketones, thus providing a simple and highly regio- and stereoselective synthesis of the latter.The addition of a second equivalent of another alkene to the methylalkylborane gives a sequential hydroboration product, MeRARBB.This mixed trialkylborane is readily converted into the corresponding tertiary alcohol via carbonylation-oxidation.The ability to hydroborate an alkene in consecutive stages enables the regioselectivity of the first and second stages of hydroboration to be determined.Thus, the first hydroboration of 1-hexene gives a C-1/C-2 ratio of 98.5:1.5, similar to values obtained with 9-BBN and Sia2BH.The second hydroboration of cis-4-methyl-2-pentene occurs with complete regioselectivity, i.e., 100:0, surpassing the values obtained with the two aforementioned hydroborating agents.MeBH2 is the first example of a sterically nonhindered monoalkylborane capable of stepwise hydroborations of all classes of alkenes.
