111011-80-4Relevant academic research and scientific papers
Palladium-catalyzed coupling of allenylphosphonates, phenylallenes, and allenyl esters: Remarkable salt effect and routes to novel benzofurans and isocoumarins
Chakravarty, Manab,Swamy, K. C. Kumara
, p. 9128 - 9138 (2006)
(Chemical Equation Presented) Coupling reactions of allenylphosphonates (OCH2CMe2CH2O)P(O)CH=C=CRR′ [R, R′ = H (1a), R = H, R′ = Me (1b), R = R′ = Me (1c)] with aryl iodides, iodophenol, and iodobenzoic acid in the presence of palladium(II) acetate are investigated and compared with those of phenylallenes PhCH=C=CR2 [R = H (2a), Me (2b)] and allenyl esters EtO2CCH=C=CR2 [R = H (2c), Me (2d)]. While 1b and 1c couple with different stereochemical outcomes using PhI in the presence of Pd(OAc)2/PPh3/K 2CO3 to give phenyl-substituted 1,3-butadienes, 1a does not undergo coupling but isomerizes to the acetylene (OCH2CMe 2CH2O)P(O)C≡CMe (7). In the reaction of 1c with PhI, use of K2CO3 affords the butadiene (Z)-(OCH 2CMe2CH2O)P(O)CH=C(Ph)-C(Me)=CH2 (12); in contrast, the use of Ag2CO3 leads to the allene (OCH2CMe2CH2O)P(O)C(Ph)=C=CMe2 (20), showing that these bases differ very significantly in their roles. The reaction of 1a with PhI or PhB(OH)2 in the presence of Pd(OAc) 2/CsF/DMF leads mainly to (E)-(OCH2CMe2CH 2O)P(O)CH=C(Me)Ph (21) and (OCH2CMe2CH 2O)P(O)CH2-C(Ph)=CH2 (22) and is thus a net 1,2-addition of Ph-H. Compound 1b reacts with iodophenol in the presence of Pd(OAc)2/PPh3/K2CO3 to give a benzofuran that has a structure different from that obtained by using 1c under similar conditions. Treatment of 1a with iodophenol/Pd(OAc)2/CsF/DMF also gives a benzofuran whose structure is different from that obtained by using 2a under similar conditions. In the reaction with 2-iodobenzoic acid, 1a and 2c afford one type of isocoumarin, while 1b,c and 2a,b give a second type of isocoumarin. The structures of key compounds are established by X-ray crystallography. Utility of the phosphonate products in the Horner-Wadsworth- Emmons reaction is demonstrated.
Reaction of allenylphosphonates/allenylphosphine oxides with thiocyanates/isothiocyanates or oxalyl chloride/AgNO3
Swamy, K. C. Kumara,Chakravarty, Manab,Debnath, Shubham,Reddy, M. Nagarjuna
, p. 763 - 768 (2017)
In this paper, we describe thiocyanation as well as chlorination of selected allenylphosphonates/allenyl phosphine oxide, using ammonium thiocaynate or (OCH2CMe2CH2O)PNCS (for thiocyanation) or oxalyl chloride/AgNO3/
New reactions of allenes, alkynes, ynamides, enynones and isothiocyanates
Swamy, K C Kumara,Gangadhararao,Anitha, Mandala,Sivakumari, A Leela,Reddy, Alla Siva,Kalyani, Adula,Allu, Srinivasarao
, (2018/07/25)
Abstract: This perspective article is related to transformations (both catalytic and non-catalytic) involving allenes, alkynes/enynones/ynamides and isothiocyanates. Part of the work from the author’s group has been reviewed along with some new reactions of (i) allenylphosphonate/allenylphosphine oxide and (ii) a P(III) isothiocyanate. Thus, the allenylphosphine oxide Ph 2P(O)C(Ph)=C=CH 2 undergoes base (DBU) catalyzed addition to the β-ketophosphonate (OCH 2CMe 2CH 2O)P(O)CH 2C(O)CH 3 at 90°C to afford the addition product Ph 2P(O)C(Ph)=C(Me)CH[C(O)Me][P(O)(OCH 2CMe 2CH 2O)]. In an analogous reaction, with DBU as the base at 140°C, isomeric vinylphosphine oxides (Z)-Ph 2P(O)C(Ph)=C(Me)CH 2[C(O)Me] and (E)-Ph 2P(O)C(Ph)=C(Me)CH 2[C(O)Me] were isolated. The E-isomer has been characterized by single crystal X-ray structure determination. In another set of studies, the reaction of P(III) isothiocyanate (OCH 2CMe 2CH 2O)P(NCS) with N-(2-bromomethyl)sulfonamide afforded an unusual product with the formula (OCH 2CMe 2CH 2O)P(O)SCH 2CH 2NHS(O) 2-(C 6H 4-4-Me) as shown by X-ray structure determination. This result is different from that obtained in the recently reported analogous reaction using phenyl isothiocyanate. Graphical Abstract: Synopsis. Base-catalyzed the addition of β-ketophosphonate or ethyl acetoacetate to allenylphosphine oxide affords vinylphosphine oxides; in the latter case, elimination of the ester group also takes place. It is also shown that reactivity of a P(III) isothiocyanate is different from that of organic isothiocyanates. [Figure not available: see fulltext.].
Hydrazine derivatives useful as intermediates in the synthesis of hypotensive agents
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, (2008/06/13)
A hydrazine derivative having the formula: STR1 wherein R is a hydrogen atom or STR2
Synthesis of 1,4-dihydropyridine-5-phosphonates and their calcium-antagonistic and antihypertensive activities
Sakoda,Kamikawaji,Seto
, p. 2362 - 2369 (2007/10/02)
The effect of the 3-carboxylic-ester variation in 2,2-dimethyltrimethylene 3-alkoxycarbonyl-4-aryl-1,4-dihydro-2,6-dimethyl-5-pyridinephosphonate s (1) was investigated with relation to the calcium-antagonistic and antihypertensive activities: the analogs containing the alkyl groups of not more than 12 carbons and an amino functionality in the carboxylic-ester moiety were synthesized to be examined for biological activities. Among them, 2-[benzyl(phenyl)amino]-ethyl 5-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,4-dihydro-2,6-di methyl-4-(3-nitrophenyl)-3-pyridine-carboxylate hydrochloride ethanol (NZ-105) showed particularly beneficial activities and was selected for further pharmacological studies and clinical development. Some aspects of the structure-activity relationships and solid-state structure of NZ-105 by X-ray crystallographic analysis were described.
Reaction of Cyclic Silyl Phosphites with Haloacetones
Morita, Iwao,Chokai, Shoichi,Tsuda, Masami,Kise, Masahiro,Sugiyama, Makoto
, p. 1135 - 1138 (2007/10/02)
The reaction of cyclic silyl phosphites (2) with haloacetones (3) was investigated.When oxirane compounds were used as scavengers of trimethylsilyl halides, cyclic acetonylphosphonates (4) were obtained directly.Treatment of 2-trimethylsilyloxy-1,3,2-dioxaphosphorinane (2a) with bromoacetone (3b) or iodoacetone (3c) in propylene oxide gave 4a in 24 percent and 41 percent yields, respectively.With cyclohexane oxide, the reaction of 2a with 3c in MeCN at reflux gave 4a in 50 percent yield.Treatment of 5,5-dimethyl-2-trimethylsilyloxy-1,3,2-dioxaphosphorinane (2b) with 3c in the same manner gave 4b in 43 percent yield.Keywords - cyclic silyl phosphite; haloacetone; cyclic acetonylphosphonate; enolphosphate; Arbuzov reaction; Perkow reaction; carbonyl adduct; trimethylsilyl halide scavenger
Reaction of Cyclic Phosphites with Haloacetones
Morita, Iwao,Tsuda, Masami,Kise, Masahiro,Sugiyama, Makoto
, p. 4711 - 4716 (2007/10/02)
Treatment of various cyclic phosphites (1), e.g.,2-methoxy-1,3,2-dioxaphosphorinane (1a), 2-methoxy-5,5-dimethyl-1,3,2-dioxaphosphorinane (1b) and 2-methoxy-1,3,2-dioxaphosphorane (1c), with haloacetones (2) gave cyclic Arbuzov products (3), cyclic Perkow products (4), cyclic methylphosphonates (5), and acyclic products (6-8).Compound 1a gave all of the products (3a,4a,5a,6ag,7ag,8ag).However, cyclic phosphites with substituents in the ring (1b,1d) gave only the cyclic products (3-5).The five -membered ring phosphite (1c) yielded only the acyclic products (6cg, 7cg).Treatment of 1a with chloroacetone gave only the Perkow products (4a,7ah).Cyclic phosphite (1f)with 2-benzyloxy substituenet afforded simply the cyclic products (3a, 4a, 9).A mechanistic interpretation of these reactions is presented. Keywords---cyclic phosphite; haloacetone; cyclic acetonylphosphonate; cyclic enol phosphate; Arbuzov reaction; Perkow reaction
