Question

Bruce Lipshutz used Merrifield resin to scavenge this molecule and its tricky-to-separate oxidized derivative after reactions using Ni(0) (“nickel-zero”). Adding an acyl group to this molecule, rather than an ester, allows it to be cleaved during a reaction’s “traceless” variant. Four copies (-5[1])of this molecule are ligands on a tetrahedral complex that supplies palladium to cross-couplings. (10[1])An excess (-5[1])of this molecule is separated alongside waste hydrazines in a reaction in which it prepares an alcohol for (10[1])SN2 substitution after attacking the azo group of DIAD (“D-I-A-D”). This molecule is the (10[1])bulkiest ligand on Wilkinson’s catalyst. (10[5])This molecule lies (10[1])at one corner (-5[1])of the square intermediate formed (10[1])by a carbonyl and an ylide (10[1])(“ILL-id”). This molecule is a key reagent in both the Mitsunobu and Wittig reactions. For 10 points, name this bulky compound with three aryl (10[1])groups (10[1])bound to phosphorus. (10[1]0[1])■END■ (10[4]0[2])

ANSWER: triphenylphosphine (“tri-phenyl-phosphine”) [accept Ph3PO, triphenylphosphine oxide, triphenylphosphonium ylide, or tetrakis(triphenylphosphine) palladium(0); prompt on TPPO by asking “what does that stand for?”]
<Chemistry>
= Average correct buzz position