Synthesis of Dihydrophosphepin 1-Oxides by Ring Enlargement†

Synthesis and cation binding ability of azacrown ethers with phosphine or phosphine oxide side chain

“…(3c) Yield 51%; 31 P and 13 C NMR, (3b) Yield 53%; spectroscopical data were similar to those reported earlier [1].…”

“…The 31 P and 13 C NMR parameters are listed in Table 1. The chemical shifts, couplings, and mass spectroscopic fragmentation of phosphine oxides 3 showed close resemblance to the SCHEME 1 SCHEME 2 corresponding features of phosphinic esters described earlier [1].…”

“…The reaction of crown 1 with diphenylvinylphosphine oxide in boiling methanol, in the presence of a catalytic amount of acetic acid, however, led to product 3a in excellent yield (92%) (Scheme 2). With the exception of 3b [1], the lariat ethers (3a,c,d) that were synthesized are new compounds and have been characterized by 31 P, 13 C, and 1 H NMR, as well as mass spectrometry (MS) and high-resolution mass spectrometry (HRMS) data. The 31 P and 13 C NMR parameters are listed in Table 1.…”

“…In continuation of our current interest in the synthesis of macrocycles with phosphorus containing side chains [1,2], we present the preparation of the phosphine and the phosphine oxide derivatives of monoaza-15-crown-5. The few examples of monoaza-and diazacrown ethers with phosphorus containing side arm(s) described include phosphonomethyl-and phosphinoalkyl derivatives [3][4][5].…”

Selective reductions in the sphere of organophosphorus compounds

“…of cyclic vinyl phosphine oxides (1, Y‫ס‬Ph) and phosphinates (1, Y‫ס‬OR) (Scheme 1) [1][2]. The reduced product 3 is formed through hydroboration.…”