Non-covalent organocatalyzed enantioselective cyclization reactions of α,β-unsaturated imines

• Sergio Torres-Oya and
• Mercedes Zurro

Beilstein J. Org. Chem. 2024, 20, 3221–3255, doi:10.3762/bjoc.20.268

• carbamate group by interaction with the oxygen atom of the phosphoryl group. Although recently Rana and co-workers published a review article covering catalytic asymmetric transformations of azadienes [16], there is still room for this review which only focuses on non-covalent organocatalyzed cyclizations

• enantioselectivities (92–96% ee). The proposed reaction pathway is depicted in Scheme 30, the phosphoric acid simultaneously activates the azadiene through hydrogen bonding and the azlactone which is converted to its enol form establishing hydrogen bonding with the phosphoryl group. Next, the 1,4-addition of the

Convenient access to pyrrolidin-3-ylphosphonic acids and tetrahydro-2H-pyran-3-ylphosphonates with multiple contiguous stereocenters from nonracemic adducts of a Ni(II)-catalyzed Michael reaction

• Alexander N. Reznikov,
• Dmitry S. Nikerov,
• Anastasiya E. Sibiryakova,
• Victor B. Rybakov,
• Evgeniy V. Golovin and
• Yuri N. Klimochkin

Beilstein J. Org. Chem. 2020, 16, 2073–2079, doi:10.3762/bjoc.16.174

• Micromonospora [5]. Dipeptide analogs with phosphonoproline 2 and piperidine-2-phosphonic acid 3 are potent inhibitors of dipeptidyl peptidase IV [6][7]. Oxygen-containing heterocycles containing a phosphoryl group are also of interest in the development of new drugs. It is known that phosphorylated carbohydrate

• presence of Pd/C. However, phosphonate 7 was unstable: already during its isolation, it was partially transformed into compounds 8 and 9. It can be assumed that N-alkylation by the phosphoryl group occurs [47][48][49]. To avoid this undesirable process, the product 7 was formylated before its isolation

The McKenna reaction – avoiding side reactions in phosphonate deprotection

• Katarzyna Justyna,
• Joanna Małolepsza,
• Damian Kusy,
• Waldemar Maniukiewicz and
• Katarzyna M. Błażewska

Beilstein J. Org. Chem. 2020, 16, 1436–1446, doi:10.3762/bjoc.16.119

• compounds, with one representing the phosphonate, and the other containing a functional group, which could undergo a side reaction under the reaction conditions. As the first class of compounds, representing the phosphoryl group, we used phosphonates 8 and 9 (Figure 1). As the second class of model

[1,3]/[1,4]-Sulfur atom migration in β-hydroxyalkylphosphine sulfides

• Katarzyna Włodarczyk,
• Piotr Borowski and
• Marek Stankevič

Beilstein J. Org. Chem. 2020, 16, 88–105, doi:10.3762/bjoc.16.11

• ketophosphonates from vinylphosphates [53]. [1,4]-Rearrangements include that of o-phosphorus-substituted benzyl carbanions [34], phosphorus group migration in O-phosphorylated 1,4-benzodiazepines [54], or phosphoryl group carbon-to-oxygen transfer [55]. The common feature of every rearrangement presented above is

Functionalization of the imidazo[1,2-a]pyridine ring in α-phosphonoacrylates and α-phosphonopropionates via microwave-assisted Mizoroki–Heck reaction

• Damian Kusy,
• Agata Wojciechowska,
• Joanna Małolepsza and
• Katarzyna M. Błażewska

Beilstein J. Org. Chem. 2020, 16, 15–21, doi:10.3762/bjoc.16.3

• composed of both, an imidazo[1,2-a]pyridine ring and the phosphoryl group. The combination of these functional groups can be found in bisphosphonates and phosphonocarboxylates [8][9][10] – inhibitors of the therapeutically important enzymes, farnesyl pyrophosphate synthase (FPPS) and Rab geranylgeranyl

Synthesis of ([1,2,4]triazolo[4,3-a]pyridin-3-ylmethyl)phosphonates and their benzo derivatives via 5-exo-dig cyclization

• Aleksandr S. Krylov,
• Artem A. Petrosian,
• Julia L. Piterskaya,
• Nataly I. Svintsitskaya and
• Albina V. Dogadina

Beilstein J. Org. Chem. 2019, 15, 1563–1568, doi:10.3762/bjoc.15.159

• available N-unsubstituted 2-hydrazinylpyridines and 2(1)-hydrazinyl(iso)quinolines. Due to the presence of the fused [1,2,4]triazole hetaryl pharmacophore fragment and a phosphoryl group in the obtained compounds they are of great interest as promising substances with potential biological activity

Different reactivity of phosphorylallenes under the action of Brønsted or Lewis acids: a crucial role of involvement of the P=O group in intra- or intermolecular interactions at the formation of cationic intermediates

• Stanislav V. Lozovskiy,
• Alexander Yu. Ivanov and
• Aleksander V. Vasilyev

Beilstein J. Org. Chem. 2019, 15, 1491–1504, doi:10.3762/bjoc.15.151

• ; oxaphospholium ions; phosphorylallenes; phosphoryl group; triflic acid; Introduction Electrophilic reactions of allenes have been intensely explored in organic synthesis [1][2][3]. In particular, reports on electrophilic activation of phosphorylallenes are numerous [4][5][6][7][8][9][10]. Miscellaneous

• phosphoryl group: chloro (1a–d), amino (1e–g), arylsulfanyl (1h,i), and methoxy (1j). Results and Discussion Reactions of allenes with Brønsted acids Allenes 1a,b,e–j upon dissolving in TfOH in an NMR tube at room temperature formed intensively colored solutions of the corresponding 1,2-oxaphospholium ions A

Phenylsilane as an effective desulfinylation reagent

• Wanda H. Midura,
• Aneta Rzewnicka and
• Jerzy A. Krysiak

Beilstein J. Org. Chem. 2017, 13, 1513–1517, doi:10.3762/bjoc.13.150

• reduction of the ester group. In both cyclopropanes the carboxylate moiety and the sulfinyl group were in vicinal relation, but in 1, formed in the reaction of vinyl phosphoryl sulfoxide with EDSA [22], the ester group was easily accessed, since the bulky phosphoryl group was also in vicinal position to the

Relay cross metathesis reactions of vinylphosphonates

• Raj K. Malla,
• Jeremy N. Ridenour and
• Christopher D. Spilling

Beilstein J. Org. Chem. 2014, 10, 1933–1941, doi:10.3762/bjoc.10.201

• undergo palladium-catalyzed addition of nucleophiles to give γ-substituted vinylphosphonates 2 in high yield (Scheme 1). The nucleophile adds exclusively to the 3-position, with migration of the double bond into “conjugation” with phosphoryl group. As expected, the reactions generally proceed with

Methylidynetrisphosphonates: Promising C₁ building block for the design of phosphate mimetics

• Vadim D. Romanenko and
• Valery P. Kukhar

Beilstein J. Org. Chem. 2013, 9, 991–1001, doi:10.3762/bjoc.9.114

• -toluenesulfonate or dimethyl sulfate leads to the expected quarternary ammonium salts 40, while with iodomethane one phosphoryl group is split off, and a mixture of bisphosphonates 41 and 42 is formed (Scheme 21) [20]. In a fascinating series of publications, Blackburn and co-workers have realized the synthesis of

Kinetic studies and predictions on the hydrolysis and aminolysis of esters of 2-S-phosphorylacetates

• Milena Trmčić and
• David R. W. Hodgson

Beilstein J. Org. Chem. 2010, 6, 732–741, doi:10.3762/bjoc.6.87

• the nature of the thiophosphate group in the 2-position of the ester, we may also consider the possibility of intramolecular nucleophilic catalysis where an oxygen atom of the phosphoryl group displaces the ester leaving group to form a cyclic mixed carboxylic-phosphoric acid anhydride (Scheme 6B