Wang Ge, Guino-o Marites A, Glueck David S, Golen James A, Daley Christopher J A, Rheingold Arnold L
6128 Burke Laboratory, Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, USA.
Dalton Trans. 2015 Jun 7;44(21):9943-54. doi: 10.1039/c5dt00520e.
Metal-mediated synthesis of a new heterocycle, 1-phenyl-phosphapyracene (Ph-4, Ph-PyraPhos), by tandem phosphination/cyclization of peri-substituted 5-bromo-6-chloromethylacenaphthene (3) was investigated for comparison to Pt-catalyzed formation of 1-phosphaacenaphthenes (2, AcePhos) from the analogous naphthalene precursor (1). Reaction of PH2Ph with , NaOSiMe3 and a Cu catalyst gave ; a Pt catalyst yielded PHPh(CH2Ar) (Ph-11, Ar = 5-Br-acenaphthyl). Deprotonation of a complex of this secondary phosphine, [Pt((R,R)-Me-DuPhos)(Ph)(PHPh(CH2Ar))][PF6] (17), generated the phosphido intermediate Pt((R,R)-Me-DuPhos)(Ph)(PPhCH2Ar) (Ph-8), which cyclized to give [Pt((R,R)-Me-DuPhos)(Ph)(Ph-PyraPhos)][PF6] (18). Treatment of P-8 with silver triflate gave 18 and the cyclometalated phosphine complex [Pt((R,R)-Me-DuPhos)(κ(2)-(P,C)-5-Ph2PCH2-6-C12H8)][PF6] (21), which might form via Pt(iv) intermediates. The effects of the added "ace" bridge on structure and reactivity are discussed.
研究了通过周位取代的5-溴-6-氯甲基苊（3）的串联膦化/环化反应，以金属介导合成新的杂环化合物1-苯基-磷杂并四苯（Ph-4，Ph-PyraPhos），并与由类似萘前体（1）经铂催化形成1-磷杂苊（2，AcePhos）的反应进行比较。PH2Ph与NaOSiMe3及铜催化剂反应得到[具体产物未明确给出]；铂催化剂则生成PHPh(CH2Ar)（Ph-11，Ar = 5-溴-苊基）。该仲膦配合物[Pt((R,R)-Me-DuPhos)(Ph)(PHPh(CH2Ar))][PF6]（17）去质子化生成磷化物中间体Pt((R,R)-Me-DuPhos)(Ph)(PPhCH2Ar)（Ph-8），其环化得到[Pt((R,R)-Me-DuPhos)(Ph)(Ph-PyraPhos)][PF6]（18）。用三氟甲磺酸银处理P-8得到18和环金属化膦配合物[Pt((R,R)-Me-DuPhos)(κ(2)-(P,C)-5-Ph2PCH2-6-C12H8)][PF6]（21），后者可能通过Pt(IV)中间体形成。讨论了引入的“ace”桥对结构和反应性的影响。
