P(i-BuNCH₂CH₂)₃N:  An Efficient Promoter for the Nucleophilic Aromatic Substitution Reaction of Aryl Fluorides with Aryl TBDMS (or TMS) Ethers

Abstract

[reaction: see text]. The nucleophilic aromatic substitution reaction between electron-deficient aryl fluorides and aryl TBDMS (or TMS) ethers has been shown to be efficiently promoted by proazaphosphatranes such as P(i-BuNCH(2)CH(2))(3)N (3). Excellent yields of diaryl ether products were obtained under unusually mild conditions.

Chimeric derivatives of functionalized amino acids and α-aminoamides: Compounds with anticonvulsant activity in seizure models and inhibitory actions on central, peripheral, and cardiac isoforms of voltage-gated sodium channels

“…The substituted 4-phenoxybenzylamines were prepared by treating 4-fluorobenzonitrile ( 10 ) with the appropriate aryl phenol ( 11 – 15 ) using either K 2 CO 3 or Cs 2 CO 3 in DMF to give the corresponding nitriles. 24–27 Subsequent reduction of the nitrile group in 16 – 20 with LiAIH 4 afforded the amines 22 – 26 . The corresponding unsubstituted 4-phenoxybenzylamine ( 21 ) was commercially available.…”

“…Using Method 1, ( R )- 34 (1.27 g, 3.17 mmol), 4 M HCl (5.6 mL), Et 3 N (962 mg, 9.51 mmol), and AcCl (298 mg, 3.80 mmol) gave the desired compound ( R )- 3 as a white solid (981 mg, 90%): R f = 0.27 (20:1 CH 2 Cl 2 /MeOH); mp 147–148 °C; [α] D 24 –16.1° ( c 1.0, CHCl 3 ); 1 H NMR (CDCl 3 ) δ 2.03 (s, C H 3 C(O)), 3.39 (s, OC H 3 ), 3.46 (dd, J = 4.3, 9.3 Hz, C H H′OCH 3 ), 3.81 (dd, J = 4.3, 9.3 Hz, CH H ′OCH 3 ), 4.40–4.48 (m, NHC H 2 ), 4.58 (dt, J = 4.3, 7.0 Hz, C H CH 2 ), 6.49 (d, J = 7.0 Hz, N H ), 6.83–6.93 (m, 2 Ar H , N H ), 6.93–6.97 (m, Ar H ), 7.00 (d, J = 8.2 Hz, 2 Ar H ), 7.27 (d, J = 8.2 Hz, 2 Ar H ), 7.32 (m, 2 Ar H ), addition of excess ( R )-(−)-mandelic acid to a CDCl 3 solution of ( R )- 3 gave only one signal for the acetyl methyl and one signal for the methoxy protons; 13 C NMR (CDCl 3 ) δ 23.2 (C(O) C H 3 ), 43.0 (NH C H 2 ), 52.4 ( C HCH 2 ), 59.1 (O C H 3 ), 71.6 (CH C H 2 ), 118.9, 119.0, 123.3, 128.9, 132.7, 156.7 (Ar C ), 169.9, 170.3 (2 C (O)), the remaining two aromatic peaks were not detected and are believed to overlap with nearby signals; LRMS (ESI + ) 365.1 [M+Na] + (calcd for C 19 H 22 N 2 O 4 Na + 365.1); HRMS (ESI + ) 365.1478 [M+Na] + (calcd for C 19 H 22 N 2 O 4 Na + 365.1478); Anal. Calcd.…”

A New Step Towards Solid Base Catalysis: Azidoproazaphosphatranes Immobilized in Nanopores of Mesoporous Silica

“…[16][17][18][19][20][21][22][23][24][25] We have defined the term "superbase" according to Caubres definition: the term "superbase" should only be applied to bases resulting from a mixing of two (or more) bases leading to new basic species possessing their inherent new properties. The term superbase does not mean a base thermodynamically and/or kinetically stronger than another.…”

P(i-PrNCH2CH2)3N: an efficient catalyst for TMS-1,3-dithiane addition to aldehydes

“…15b We previously reported reactions in which proazaphosphatranes can activate silicon functionalities, 17-23 as for example in the silylation of alcohols using tert-butyldimethylsilyl chloride, 17,18 the synthesis of cyanohydrins via the addition of a trialkylsilylcyanide to carbonyl compounds, 19,20 the desilylation of TBDMS ethers, 21 and the nucleophilic aromatic substitution of aryl fluorides with aryl silylethers. 22,23 Because proazaphosphatranes can activate silicon functional groups [17][18][19][20][21][22][23] in addition to functioning as strong Lewis bases, 15,16 it occurred to us that in view of the paucity of reports in which the catalytic activation of TMS-dithiane for carbonyl umpolung 13,14 has been utilized, proazaphosphatranes might function well in such reactions. Here we report the use of a proazaphosphatrane as an efficient catalyst for 1,3-dithiane addition to the carbonyl of aldehydes as shown in Scheme 1.…”